diff --git a/make/java/java/FILES_java.gmk b/make/java/java/FILES_java.gmk
index 58c7b13608c37710a488848fb85e60f444d990f0..f9dd26383cefd0294770b7c8b8ef08521bdd2689 100644
--- a/make/java/java/FILES_java.gmk
+++ b/make/java/java/FILES_java.gmk
@@ -250,6 +250,8 @@ JAVA_JAVA_java = \
java/util/IdentityHashMap.java \
java/util/EnumMap.java \
java/util/Arrays.java \
+ java/util/TimSort.java \
+ java/util/ComparableTimSort.java \
java/util/ConcurrentModificationException.java \
java/util/ServiceLoader.java \
java/util/ServiceConfigurationError.java \
diff --git a/make/tools/CharsetMapping/IBM420.c2b b/make/tools/CharsetMapping/IBM420.c2b
index 6cb38028124b2cc13c455b9bc686a86eaad06221..7e0c201b41b9f7d46e3160a3bc6f9d45898b7444 100644
--- a/make/tools/CharsetMapping/IBM420.c2b
+++ b/make/tools/CharsetMapping/IBM420.c2b
@@ -1 +1,187 @@
-0x15 U+0085
+#
+# The diff of 01A434B0.TXMAP110 and 34B001A4.RXMAP110
+#
+# Added: 0x15 U+0085
+#
+0x15 U+0085
+0x42 U+FE7C
+0x46 U+FE80
+0x47 U+FE81
+0x49 U+FE83
+0x4B U+066C
+0x4B U+FF0E
+0x4C U+FF1C
+0x4D U+FF08
+0x4E U+FF0B
+0x4F U+FF5C
+0x50 U+FF06
+0x52 U+FE85
+0x52 U+FE86
+0x55 U+FE89
+0x55 U+FE8A
+0x55 U+FE8B
+0x55 U+FE8C
+0x56 U+0625
+0x56 U+FE87
+0x56 U+FE8D
+0x57 U+FE88
+0x58 U+FE8F
+0x58 U+FE90
+0x59 U+FE92
+0x5A U+FF01
+0x5B U+FF04
+0x5C U+066D
+0x5C U+FF0A
+0x5D U+FF09
+0x5E U+FF1B
+0x60 U+FF0D
+0x61 U+FF0F
+0x62 U+FE93
+0x62 U+FE94
+0x63 U+FE95
+0x63 U+FE96
+0x64 U+FE98
+0x65 U+FE99
+0x65 U+FE9A
+0x66 U+FE9C
+0x67 U+FE9D
+0x67 U+FE9E
+0x68 U+FEA0
+0x69 U+FEA1
+0x69 U+FEA2
+0x6B U+066B
+0x6B U+FF0C
+0x6C U+066A
+0x6C U+FF05
+0x6D U+FF3F
+0x6E U+FF1E
+0x6F U+FF1F
+0x70 U+FEA4
+0x71 U+FEA5
+0x71 U+FEA6
+0x72 U+FEA8
+0x73 U+FEA9
+0x73 U+FEAA
+0x74 U+FEAB
+0x74 U+FEAC
+0x75 U+FEAD
+0x75 U+FEAE
+0x76 U+FEAF
+0x76 U+FEB0
+0x77 U+FEB1
+0x77 U+FEB2
+0x78 U+FEB4
+0x7A U+FF1A
+0x7B U+FF03
+0x7C U+FF20
+0x7D U+FF07
+0x7E U+FF1D
+0x7F U+FF02
+0x80 U+FEB5
+0x80 U+FEB6
+0x81 U+FF41
+0x82 U+FF42
+0x83 U+FF43
+0x84 U+FF44
+0x85 U+FF45
+0x86 U+FF46
+0x87 U+FF47
+0x88 U+FF48
+0x89 U+FF49
+0x8A U+FEB8
+0x8B U+FEB9
+0x8B U+FEBA
+0x8C U+FEBC
+0x8D U+FEBD
+0x8D U+FEBE
+0x8E U+FEC0
+0x8F U+FEC1
+0x8F U+FEC2
+0x8F U+FEC3
+0x8F U+FEC4
+0x90 U+FEC5
+0x90 U+FEC6
+0x90 U+FEC7
+0x90 U+FEC8
+0x91 U+FF4A
+0x92 U+FF4B
+0x93 U+FF4C
+0x94 U+FF4D
+0x95 U+FF4E
+0x96 U+FF4F
+0x97 U+FF50
+0x98 U+FF51
+0x99 U+FF52
+0x9A U+FEC9
+0x9E U+FECD
+0xA2 U+FF53
+0xA3 U+FF54
+0xA4 U+FF55
+0xA5 U+FF56
+0xA6 U+FF57
+0xA7 U+FF58
+0xA8 U+FF59
+0xA9 U+FF5A
+0xAB U+FED1
+0xAB U+FED2
+0xAC U+FED4
+0xAD U+FED5
+0xAD U+FED6
+0xAE U+FED8
+0xAF U+FED9
+0xAF U+FEDA
+0xB0 U+FEDC
+0xB1 U+FEDD
+0xB1 U+FEDE
+0xB8 U+FEF9
+0xB9 U+FEFA
+0xBA U+FEE0
+0xBB U+FEE1
+0xBB U+FEE2
+0xBC U+FEE4
+0xBD U+FEE5
+0xBD U+FEE6
+0xBE U+FEE8
+0xBF U+FEE9
+0xBF U+FEEA
+0xC1 U+FF21
+0xC2 U+FF22
+0xC3 U+FF23
+0xC4 U+FF24
+0xC5 U+FF25
+0xC6 U+FF26
+0xC7 U+FF27
+0xC8 U+FF28
+0xC9 U+FF29
+0xCF U+FEED
+0xCF U+FEEE
+0xD1 U+FF2A
+0xD2 U+FF2B
+0xD3 U+FF2C
+0xD4 U+FF2D
+0xD5 U+FF2E
+0xD6 U+FF2F
+0xD7 U+FF30
+0xD8 U+FF31
+0xD9 U+FF32
+0xDA U+FEEF
+0xDC U+FEF1
+0xDE U+FEF4
+0xE2 U+FF33
+0xE3 U+FF34
+0xE4 U+FF35
+0xE5 U+FF36
+0xE6 U+FF37
+0xE7 U+FF38
+0xE8 U+FF39
+0xE9 U+FF3A
+0xF0 U+FF10
+0xF1 U+FF11
+0xF2 U+FF12
+0xF3 U+FF13
+0xF4 U+FF14
+0xF5 U+FF15
+0xF6 U+FF16
+0xF7 U+FF17
+0xF8 U+FF18
+0xF9 U+FF19
diff --git a/make/tools/CharsetMapping/IBM420.map b/make/tools/CharsetMapping/IBM420.map
index d4ce19249b3dd74cf9c3707f2401c1d394eec7cd..f4f78533d272a15879f711cb2dc26e4451efb35c 100644
--- a/make/tools/CharsetMapping/IBM420.map
+++ b/make/tools/CharsetMapping/IBM420.map
@@ -1,257 +1,253 @@
-#Generated from IBM420.java
-0x00 U+0000
-0x01 U+0001
-0x02 U+0002
-0x03 U+0003
-0x04 U+009c
-0x05 U+0009
-0x06 U+0086
-0x07 U+007f
-0x08 U+0097
-0x09 U+008d
-0x0a U+008e
-0x0b U+000b
-0x0c U+000c
-0x0d U+000d
-0x0e U+000e
-0x0f U+000f
-0x10 U+0010
-0x11 U+0011
-0x12 U+0012
-0x13 U+0013
-0x14 U+009d
-0x15 U+000a
-0x16 U+0008
-0x17 U+0087
-0x18 U+0018
-0x19 U+0019
-0x1a U+0092
-0x1b U+008f
-0x1c U+001c
-0x1d U+001d
-0x1e U+001e
-0x1f U+001f
-0x20 U+0080
-0x21 U+0081
-0x22 U+0082
-0x23 U+0083
-0x24 U+0084
-0x25 U+000a
-0x26 U+0017
-0x27 U+001b
-0x28 U+0088
-0x29 U+0089
-0x2a U+008a
-0x2b U+008b
-0x2c U+008c
-0x2d U+0005
-0x2e U+0006
-0x2f U+0007
-0x30 U+0090
-0x31 U+0091
-0x32 U+0016
-0x33 U+0093
-0x34 U+0094
-0x35 U+0095
-0x36 U+0096
-0x37 U+0004
-0x38 U+0098
-0x39 U+0099
-0x3a U+009a
-0x3b U+009b
-0x3c U+0014
-0x3d U+0015
-0x3e U+009e
-0x3f U+001a
-0x40 U+0020
-0x41 U+00a0
-0x42 U+fe7c
-0x43 U+fe7d
-0x44 U+0640
-0x45 U+f8fc
-0x46 U+fe80
-0x47 U+fe81
-0x48 U+fe82
-0x49 U+fe83
-0x4a U+00a2
-0x4b U+002e
-0x4c U+003c
-0x4d U+0028
-0x4e U+002b
-0x4f U+007c
-0x50 U+0026
-0x51 U+fe84
-0x52 U+fe85
-0x53 U+fffd
-0x54 U+fffd
-0x55 U+fe8b
-0x56 U+fe8d
-0x57 U+fe8e
-0x58 U+fe8f
-0x59 U+fe91
-0x5a U+0021
-0x5b U+0024
-0x5c U+002a
-0x5d U+0029
-0x5e U+003b
-0x5f U+00ac
-0x60 U+002d
-0x61 U+002f
-0x62 U+fe93
-0x63 U+fe95
-0x64 U+fe97
-0x65 U+fe99
-0x66 U+fe9b
-0x67 U+fe9d
-0x68 U+fe9f
-0x69 U+fea1
-0x6a U+00a6
-0x6b U+002c
-0x6c U+0025
-0x6d U+005f
-0x6e U+003e
-0x6f U+003f
-0x70 U+fea3
-0x71 U+fea5
-0x72 U+fea7
-0x73 U+fea9
-0x74 U+feab
-0x75 U+fead
-0x76 U+feaf
-0x77 U+f8f6
-0x78 U+feb3
-0x79 U+060c
-0x7a U+003a
-0x7b U+0023
-0x7c U+0040
-0x7d U+0027
-0x7e U+003d
-0x7f U+0022
-0x80 U+f8f5
-0x81 U+0061
-0x82 U+0062
-0x83 U+0063
-0x84 U+0064
-0x85 U+0065
-0x86 U+0066
-0x87 U+0067
-0x88 U+0068
-0x89 U+0069
-0x8a U+feb7
-0x8b U+f8f4
-0x8c U+febb
-0x8d U+f8f7
-0x8e U+febf
-0x8f U+fec3
-0x90 U+fec7
-0x91 U+006a
-0x92 U+006b
-0x93 U+006c
-0x94 U+006d
-0x95 U+006e
-0x96 U+006f
-0x97 U+0070
-0x98 U+0071
-0x99 U+0072
-0x9a U+fec9
-0x9b U+feca
-0x9c U+fecb
-0x9d U+fecc
-0x9e U+fecd
-0x9f U+fece
-0xa0 U+fecf
-0xa1 U+00f7
-0xa2 U+0073
-0xa3 U+0074
-0xa4 U+0075
-0xa5 U+0076
-0xa6 U+0077
-0xa7 U+0078
-0xa8 U+0079
-0xa9 U+007a
-0xaa U+fed0
-0xab U+fed1
-0xac U+fed3
-0xad U+fed5
-0xae U+fed7
-0xaf U+fed9
-0xb0 U+fedb
-0xb1 U+fedd
-0xb2 U+fef5
-0xb3 U+fef6
-0xb4 U+fef7
-0xb5 U+fef8
-0xb6 U+fffd
-0xb7 U+fffd
-0xb8 U+fefb
-0xb9 U+fefc
-0xba U+fedf
-0xbb U+fee1
-0xbc U+fee3
-0xbd U+fee5
-0xbe U+fee7
-0xbf U+fee9
-0xc0 U+061b
-0xc1 U+0041
-0xc2 U+0042
-0xc3 U+0043
-0xc4 U+0044
-0xc5 U+0045
-0xc6 U+0046
-0xc7 U+0047
-0xc8 U+0048
-0xc9 U+0049
-0xca U+00ad
-0xcb U+feeb
-0xcc U+fffd
-0xcd U+feec
-0xce U+fffd
-0xcf U+feed
-0xd0 U+061f
-0xd1 U+004a
-0xd2 U+004b
-0xd3 U+004c
-0xd4 U+004d
-0xd5 U+004e
-0xd6 U+004f
-0xd7 U+0050
-0xd8 U+0051
-0xd9 U+0052
-0xda U+feef
-0xdb U+fef0
-0xdc U+fef1
-0xdd U+fef2
-0xde U+fef3
-0xdf U+0660
-0xe0 U+00d7
-0xe1 U+2007
-0xe2 U+0053
-0xe3 U+0054
-0xe4 U+0055
-0xe5 U+0056
-0xe6 U+0057
-0xe7 U+0058
-0xe8 U+0059
-0xe9 U+005a
-0xea U+0661
-0xeb U+0662
-0xec U+fffd
-0xed U+0663
-0xee U+0664
-0xef U+0665
-0xf0 U+0030
-0xf1 U+0031
-0xf2 U+0032
-0xf3 U+0033
-0xf4 U+0034
-0xf5 U+0035
-0xf6 U+0036
-0xf7 U+0037
-0xf8 U+0038
-0xf9 U+0039
-0xfa U+fffd
-0xfb U+0666
-0xfc U+0667
-0xfd U+0668
-0xfe U+0669
-0xff U+009f
+#
+# Frm IBMCDC datatable 01A434B0.TXMAP110
+#
+# Changed
+# 0x15 U+0085 -> 0x15 U+000a
+#
+0x00 U+0000
+0x01 U+0001
+0x02 U+0002
+0x03 U+0003
+0x04 U+009C
+0x05 U+0009
+0x06 U+0086
+0x07 U+007F
+0x08 U+0097
+0x09 U+008D
+0x0A U+008E
+0x0B U+000B
+0x0C U+000C
+0x0D U+000D
+0x0E U+000E
+0x0F U+000F
+0x10 U+0010
+0x11 U+0011
+0x12 U+0012
+0x13 U+0013
+0x14 U+009D
+0x15 U+000A
+0x16 U+0008
+0x17 U+0087
+0x18 U+0018
+0x19 U+0019
+0x1A U+0092
+0x1B U+008F
+0x1C U+001C
+0x1D U+001D
+0x1E U+001E
+0x1F U+001F
+0x20 U+0080
+0x21 U+0081
+0x22 U+0082
+0x23 U+0083
+0x24 U+0084
+0x25 U+000A
+0x26 U+0017
+0x27 U+001B
+0x28 U+0088
+0x29 U+0089
+0x2A U+008A
+0x2B U+008B
+0x2C U+008C
+0x2D U+0005
+0x2E U+0006
+0x2F U+0007
+0x30 U+0090
+0x31 U+0091
+0x32 U+0016
+0x33 U+0093
+0x34 U+0094
+0x35 U+0095
+0x36 U+0096
+0x37 U+0004
+0x38 U+0098
+0x39 U+0099
+0x3A U+009A
+0x3B U+009B
+0x3C U+0014
+0x3D U+0015
+0x3E U+009E
+0x3F U+001A
+0x40 U+0020
+0x41 U+00A0
+0x42 U+0651
+0x43 U+FE7D
+0x44 U+0640
+0x45 U+200B
+0x46 U+0621
+0x47 U+0622
+0x48 U+FE82
+0x49 U+0623
+0x4A U+00A2
+0x4B U+002E
+0x4C U+003C
+0x4D U+0028
+0x4E U+002B
+0x4F U+007C
+0x50 U+0026
+0x51 U+FE84
+0x52 U+0624
+0x55 U+0626
+0x56 U+0627
+0x57 U+FE8E
+0x58 U+0628
+0x59 U+FE91
+0x5A U+0021
+0x5B U+0024
+0x5C U+002A
+0x5D U+0029
+0x5E U+003B
+0x5F U+00AC
+0x60 U+002D
+0x61 U+002F
+0x62 U+0629
+0x63 U+062A
+0x64 U+FE97
+0x65 U+062B
+0x66 U+FE9B
+0x67 U+062C
+0x68 U+FE9F
+0x69 U+062D
+0x6A U+00A6
+0x6B U+002C
+0x6C U+0025
+0x6D U+005F
+0x6E U+003E
+0x6F U+003F
+0x70 U+FEA3
+0x71 U+062E
+0x72 U+FEA7
+0x73 U+062F
+0x74 U+0630
+0x75 U+0631
+0x76 U+0632
+0x77 U+0633
+0x78 U+FEB3
+0x79 U+060C
+0x7A U+003A
+0x7B U+0023
+0x7C U+0040
+0x7D U+0027
+0x7E U+003D
+0x7F U+0022
+0x80 U+0634
+0x81 U+0061
+0x82 U+0062
+0x83 U+0063
+0x84 U+0064
+0x85 U+0065
+0x86 U+0066
+0x87 U+0067
+0x88 U+0068
+0x89 U+0069
+0x8A U+FEB7
+0x8B U+0635
+0x8C U+FEBB
+0x8D U+0636
+0x8E U+FEBF
+0x8F U+0637
+0x90 U+0638
+0x91 U+006A
+0x92 U+006B
+0x93 U+006C
+0x94 U+006D
+0x95 U+006E
+0x96 U+006F
+0x97 U+0070
+0x98 U+0071
+0x99 U+0072
+0x9A U+0639
+0x9B U+FECA
+0x9C U+FECB
+0x9D U+FECC
+0x9E U+063A
+0x9F U+FECE
+0xA0 U+FECF
+0xA1 U+00F7
+0xA2 U+0073
+0xA3 U+0074
+0xA4 U+0075
+0xA5 U+0076
+0xA6 U+0077
+0xA7 U+0078
+0xA8 U+0079
+0xA9 U+007A
+0xAA U+FED0
+0xAB U+0641
+0xAC U+FED3
+0xAD U+0642
+0xAE U+FED7
+0xAF U+0643
+0xB0 U+FEDB
+0xB1 U+0644
+0xB2 U+FEF5
+0xB3 U+FEF6
+0xB4 U+FEF7
+0xB5 U+FEF8
+0xB8 U+FEFB
+0xB9 U+FEFC
+0xBA U+FEDF
+0xBB U+0645
+0xBC U+FEE3
+0xBD U+0646
+0xBE U+FEE7
+0xBF U+0647
+0xC0 U+061B
+0xC1 U+0041
+0xC2 U+0042
+0xC3 U+0043
+0xC4 U+0044
+0xC5 U+0045
+0xC6 U+0046
+0xC7 U+0047
+0xC8 U+0048
+0xC9 U+0049
+0xCA U+00AD
+0xCB U+FEEB
+0xCD U+FEEC
+0xCF U+0648
+0xD0 U+061F
+0xD1 U+004A
+0xD2 U+004B
+0xD3 U+004C
+0xD4 U+004D
+0xD5 U+004E
+0xD6 U+004F
+0xD7 U+0050
+0xD8 U+0051
+0xD9 U+0052
+0xDA U+0649
+0xDB U+FEF0
+0xDC U+064A
+0xDD U+FEF2
+0xDE U+FEF3
+0xDF U+0660
+0xE0 U+00D7
+0xE2 U+0053
+0xE3 U+0054
+0xE4 U+0055
+0xE5 U+0056
+0xE6 U+0057
+0xE7 U+0058
+0xE8 U+0059
+0xE9 U+005A
+0xEA U+0661
+0xEB U+0662
+0xED U+0663
+0xEE U+0664
+0xEF U+0665
+0xF0 U+0030
+0xF1 U+0031
+0xF2 U+0032
+0xF3 U+0033
+0xF4 U+0034
+0xF5 U+0035
+0xF6 U+0036
+0xF7 U+0037
+0xF8 U+0038
+0xF9 U+0039
+0xFB U+0666
+0xFC U+0667
+0xFD U+0668
+0xFE U+0669
+0xFF U+009F
diff --git a/make/tools/CharsetMapping/IBM420.nr b/make/tools/CharsetMapping/IBM420.nr
index 675451906d4bc28b66cba49593cf9c57a6a6f559..c3d93ee477439e733b8a56fe6c50b5815529b6f8 100644
--- a/make/tools/CharsetMapping/IBM420.nr
+++ b/make/tools/CharsetMapping/IBM420.nr
@@ -1 +1 @@
-0x25 U+000a
+0x25 U+000a
diff --git a/make/tools/src/build/tools/charsetmapping/GenerateSBCS.java b/make/tools/src/build/tools/charsetmapping/GenerateSBCS.java
index 5d791d515915695b4695d6193192a67bf3ffb1a6..8a57a6521bce9a439e7ef3729fe5f01b787f2f6a 100644
--- a/make/tools/src/build/tools/charsetmapping/GenerateSBCS.java
+++ b/make/tools/src/build/tools/charsetmapping/GenerateSBCS.java
@@ -26,6 +26,7 @@
package build.tools.charsetmapping;
import java.io.*;
+import java.util.Arrays;
import java.util.ArrayList;
import java.util.Scanner;
import java.util.Formatter;
@@ -54,33 +55,19 @@ public class GenerateSBCS {
String pkgName = fields[4];
System.out.printf("%s,%s,%s,%b,%s%n", clzName, csName, hisName, isASCII, pkgName);
- StringBuilder b2c = new StringBuilder();
- int c2bLen = genB2C(
- new FileInputStream(new File(args[0], clzName+".map")), b2c);
-
- String b2cNR = null;
- File nrF = new File(args[0], clzName+".nr");
- if (nrF.exists()) {
- b2cNR = genNR(new FileInputStream(nrF));
- }
-
- String c2bNR = null;
- File c2bF = new File(args[0], clzName+".c2b");
- if (c2bF.exists()) {
- c2bNR = genC2BNR(new FileInputStream(c2bF));
- }
-
- genSBCSClass(args[0], args[1], "SingleByte-X.java",
- clzName, csName, hisName, pkgName, isASCII,
- b2c.toString(), b2cNR, c2bNR, c2bLen);
+ genClass(args[0], args[1], "SingleByte-X.java",
+ clzName, csName, hisName, pkgName, isASCII);
}
}
private static void toString(char[] sb, int off, int end,
- Formatter out, String closure) {
+ Formatter out, String closure,
+ boolean comment) {
while (off < end) {
out.format(" \"");
for (int j = 0; j < 8; j++) {
+ if (off == end)
+ break;
char c = sb[off++];
switch (c) {
case '\b':
@@ -103,101 +90,124 @@ public class GenerateSBCS {
out.format("\\u%04X", c & 0xffff);
}
}
- if (off == end)
- out.format("\" %s // 0x%02x - 0x%02x%n", closure, off-8, off-1);
- else
- out.format("\" + // 0x%02x - 0x%02x%n", off-8, off-1);
+ if (comment) {
+ if (off == end)
+ out.format("\" %s // 0x%02x - 0x%02x%n",
+ closure, off-8, off-1);
+ else
+ out.format("\" + // 0x%02x - 0x%02x%n",
+ off-8, off-1);
+ } else {
+ if (off == end)
+ out.format("\"%s%n", closure);
+ else
+ out.format("\" +%n");
+ }
}
}
static Pattern sbmap = Pattern.compile("0x(\\p{XDigit}++)\\s++U\\+(\\p{XDigit}++)(\\s++#.*)?");
- private static int genB2C(InputStream in, StringBuilder out)
+
+ private static void genClass(String srcDir, String dstDir,
+ String template,
+ String clzName,
+ String csName,
+ String hisName,
+ String pkgName,
+ boolean isASCII)
throws Exception
{
- char[] sb = new char[0x100];
- int[] indexC2B = new int[0x100];
+ StringBuilder b2cSB = new StringBuilder();
+ StringBuilder b2cNRSB = new StringBuilder();
+ StringBuilder c2bNRSB = new StringBuilder();
- for (int i = 0; i < sb.length; i++)
- sb[i] = UNMAPPABLE_DECODING;
+ char[] sb = new char[0x100];
+ char[] c2bIndex = new char[0x100];
+ int c2bOff = 0;
+ Arrays.fill(sb, UNMAPPABLE_DECODING);
+ Arrays.fill(c2bIndex, UNMAPPABLE_DECODING);
- // parse the b2c mapping table
+ // (1)read in .map to parse all b->c entries
+ FileInputStream in = new FileInputStream(
+ new File(srcDir, clzName + ".map"));
Parser p = new Parser(in, sbmap);
Entry e = null;
- int off = 0;
+
while ((e = p.next()) != null) {
sb[e.bs] = (char)e.cp;
- if (indexC2B[e.cp>>8] == 0) {
- off += 0x100;
- indexC2B[e.cp>>8] = 1;
+ if (c2bIndex[e.cp>>8] == UNMAPPABLE_DECODING) {
+ c2bOff += 0x100;
+ c2bIndex[e.cp>>8] = 1;
}
}
- Formatter fm = new Formatter(out);
+ Formatter fm = new Formatter(b2cSB);
fm.format("%n");
// vm -server shows cc[byte + 128] access is much faster than
// cc[byte&0xff] so we output the upper segment first
- toString(sb, 0x80, 0x100, fm, "+");
- toString(sb, 0x00, 0x80, fm, ";");
-
+ toString(sb, 0x80, 0x100, fm, "+", true);
+ toString(sb, 0x00, 0x80, fm, ";", true);
fm.close();
- return off;
- }
- // generate non-roundtrip entries from xxx.nr file
- private static String genNR(InputStream in) throws Exception
- {
- StringBuilder sb = new StringBuilder();
- Formatter fm = new Formatter(sb);
- Parser p = new Parser(in, sbmap);
- Entry e = null;
- fm.format("// remove non-roundtrip entries%n");
- fm.format(" b2cMap = b2cTable.toCharArray();%n");
- while ((e = p.next()) != null) {
- fm.format(" b2cMap[%d] = UNMAPPABLE_DECODING;%n",
- (e.bs>=0x80)?(e.bs-0x80):(e.bs+0x80));
- }
- fm.close();
- return sb.toString();
- }
+ // (2)now the .nr file which includes "b->c" non-roundtrip entries
+ File f = new File(srcDir, clzName + ".nr");
+ if (f.exists()) {
+ in = new FileInputStream(f);
+ fm = new Formatter(b2cNRSB);
+ p = new Parser(in, sbmap);
+ e = null;
- // generate c2b only entries from xxx.c2b file
- private static String genC2BNR(InputStream in) throws Exception
- {
- StringBuilder sb = new StringBuilder();
- Formatter fm = new Formatter(sb);
- Parser p = new Parser(in, sbmap);
- ArrayList es = new ArrayList();
- Entry e = null;
- while ((e = p.next()) != null) {
- es.add(e);
+ fm.format("// remove non-roundtrip entries%n");
+ fm.format(" b2cMap = b2cTable.toCharArray();%n");
+ while ((e = p.next()) != null) {
+ fm.format(" b2cMap[%d] = UNMAPPABLE_DECODING;%n",
+ (e.bs>=0x80)?(e.bs-0x80):(e.bs+0x80));
+ }
+ fm.close();
}
- fm.format("// non-roundtrip c2b only entries%n");
- fm.format(" c2bNR = new char[%d];%n", es.size() * 2);
- int i = 0;
- for (Entry entry: es) {
- fm.format(" c2bNR[%d] = 0x%x; c2bNR[%d] = 0x%x;%n",
- i++, entry.bs, i++, entry.cp);
+ // (3)finally the .c2b file which includes c->b non-roundtrip entries
+ f = new File(srcDir, clzName + ".c2b");
+ if (f.exists()) {
+ in = new FileInputStream(f);
+ fm = new Formatter(c2bNRSB);
+ p = new Parser(in, sbmap);
+ e = null;
+ ArrayList es = new ArrayList();
+ while ((e = p.next()) != null) {
+ if (c2bIndex[e.cp>>8] == UNMAPPABLE_DECODING) {
+ c2bOff += 0x100;
+ c2bIndex[e.cp>>8] = 1;
+ }
+ es.add(e);
+ }
+ fm.format("// non-roundtrip c2b only entries%n");
+ if (es.size() < 100) {
+ fm.format(" c2bNR = new char[%d];%n", es.size() * 2);
+ int i = 0;
+ for (Entry entry: es) {
+ fm.format(" c2bNR[%d] = 0x%x; c2bNR[%d] = 0x%x;%n",
+ i++, entry.bs, i++, entry.cp);
+ }
+ } else {
+ char[] cc = new char[es.size() * 2];
+ int i = 0;
+ for (Entry entry: es) {
+ cc[i++] = (char)entry.bs;
+ cc[i++] = (char)entry.cp;
+ }
+ fm.format(" c2bNR = (%n");
+ toString(cc, 0, i, fm, ").toCharArray();", false);
+ }
+ fm.close();
}
- fm.close();
- return sb.toString();
- }
- private static void genSBCSClass(String srcDir,
- String dstDir,
- String template,
- String clzName,
- String csName,
- String hisName,
- String pkgName,
- boolean isASCII,
- String b2c,
- String b2cNR,
- String c2bNR,
- int c2blen)
- throws Exception
- {
+ // (4)it's time to generate the source file
+ String b2c = b2cSB.toString();
+ String b2cNR = b2cNRSB.toString();
+ String c2bNR = c2bNRSB.toString();
+
Scanner s = new Scanner(new File(srcDir, template));
PrintStream out = new PrintStream(new FileOutputStream(
new File(dstDir, clzName + ".java")));
@@ -239,16 +249,16 @@ public class GenerateSBCS {
line = line.replace("$B2CTABLE$", b2c);
}
if (line.indexOf("$C2BLENGTH$") != -1) {
- line = line.replace("$C2BLENGTH$", "0x" + Integer.toString(c2blen, 16));
+ line = line.replace("$C2BLENGTH$", "0x" + Integer.toString(c2bOff, 16));
}
if (line.indexOf("$NONROUNDTRIP_B2C$") != -1) {
- if (b2cNR == null)
+ if (b2cNR.length() == 0)
continue;
line = line.replace("$NONROUNDTRIP_B2C$", b2cNR);
}
if (line.indexOf("$NONROUNDTRIP_C2B$") != -1) {
- if (c2bNR == null)
+ if (c2bNR.length() == 0)
continue;
line = line.replace("$NONROUNDTRIP_C2B$", c2bNR);
}
diff --git a/src/share/classes/java/nio/channels/DatagramChannel.java b/src/share/classes/java/nio/channels/DatagramChannel.java
index cbf402f5933c3551cedb67360ed3dc58e47d957a..1dde1d7a399eb757ed4a165a4f3bb130493ce86a 100644
--- a/src/share/classes/java/nio/channels/DatagramChannel.java
+++ b/src/share/classes/java/nio/channels/DatagramChannel.java
@@ -421,7 +421,7 @@ public abstract class DatagramChannel
* invocation of this method will block until the first operation is
* complete. If this channel's socket is not bound then this method will
* first cause the socket to be bound to an address that is assigned
- * automatically, as if by invoking the {@link #bind bind) method with a
+ * automatically, as if by invoking the {@link #bind bind} method with a
* parameter of {@code null}.
*
* @param src
diff --git a/src/share/classes/java/nio/channels/package-info.java b/src/share/classes/java/nio/channels/package-info.java
index 47a1cb5f97928b316961c33070bc1c6abdd0b453..36a408402607648d6f6c60c8ce12c2ee0ae3a47d 100644
--- a/src/share/classes/java/nio/channels/package-info.java
+++ b/src/share/classes/java/nio/channels/package-info.java
@@ -115,8 +115,8 @@
* Reads, writes, maps, and manipulates files
* {@link java.nio.channels.FileLock}
* A lock on a (region of a) file
- * {@link java.nio.MappedByteBuffer}/{@link java.nio.MappedBigByteBuffer}
- * A direct byte buffer or big byte buffer mapped to a region of a file
+ * {@link java.nio.MappedByteBuffer}
+ * A direct byte buffer mapped to a region of a file
*
*
* The {@link java.nio.channels.FileChannel} class supports the usual
diff --git a/src/share/classes/java/nio/file/DirectoryStream.java b/src/share/classes/java/nio/file/DirectoryStream.java
index 001f22b0723f83e16c9663fded8af0dd409d125a..f0be02172d6a6207d43266ceea457571f6cbfa0c 100644
--- a/src/share/classes/java/nio/file/DirectoryStream.java
+++ b/src/share/classes/java/nio/file/DirectoryStream.java
@@ -53,7 +53,7 @@ import java.io.IOException;
* invoking the {@link #close close} method. Closing the directory stream
* releases any resources associated with the stream. Once a directory stream
* is closed, all further method invocations on the iterator throw {@link
- * java.util.concurrent.ConcurrentModificationException} with cause {@link
+ * java.util.ConcurrentModificationException} with cause {@link
* ClosedDirectoryStreamException}.
*
*
A directory stream is not required to be asynchronously closeable .
diff --git a/src/share/classes/java/nio/file/Path.java b/src/share/classes/java/nio/file/Path.java
index 113a7c58067ef0c1701e03fa9daa53713884ac68..d9ba6de78354e94878eefd2a055e8eeb7ff835c0 100644
--- a/src/share/classes/java/nio/file/Path.java
+++ b/src/share/classes/java/nio/file/Path.java
@@ -987,7 +987,7 @@ public abstract class Path
* exception then it is propogated to the iterator's {@link Iterator#hasNext()
* hasNext} or {@link Iterator#next() next} method. Where an {@code
* IOException} is thrown, it is propogated as a {@link
- * java.util.concurrent.ConcurrentModificationException} with the {@code
+ * java.util.ConcurrentModificationException} with the {@code
* IOException} as the cause.
*
*
When an implementation supports operations on entries in the
diff --git a/src/share/classes/java/nio/file/attribute/package-info.java b/src/share/classes/java/nio/file/attribute/package-info.java
index c5301b1f840beb97ef599c1b49b7f3e553e015ca..b2192b89237d0175f6327faf5922f118268d0552 100644
--- a/src/share/classes/java/nio/file/attribute/package-info.java
+++ b/src/share/classes/java/nio/file/attribute/package-info.java
@@ -102,9 +102,9 @@
*
The {@link java.nio.file.attribute.UserPrincipalLookupService}
* interface defines methods to lookup user or group principals.
*
- *
The {@link java.nio.file.attribute.Attribute} interface
+ *
The {@link java.nio.file.attribute.FileAttribute} interface
* represents the value of an attribute for cases where the attribute value is
- * require to be set atomically when creating an object in the file system.
+ * required to be set atomically when creating an object in the file system.
*
*
*
diff --git a/src/share/classes/java/util/Arrays.java b/src/share/classes/java/util/Arrays.java
index 313c686eb36450d2dfda598947edc50710bc5040..eac5521cd8676d7f2458c8279082246adaeab108 100644
--- a/src/share/classes/java/util/Arrays.java
+++ b/src/share/classes/java/util/Arrays.java
@@ -1065,29 +1065,103 @@ public class Arrays {
(x[b] > x[c] ? b : x[a] > x[c] ? c : a));
}
-
/**
- * Sorts the specified array of objects into ascending order, according to
- * the {@linkplain Comparable natural ordering}
- * of its elements. All elements in the array
- * must implement the {@link Comparable} interface. Furthermore, all
- * elements in the array must be mutually comparable (that is,
- * e1.compareTo(e2) must not throw a ClassCastException
- * for any elements e1 and e2 in the array).
+ * Old merge sort implementation can be selected (for
+ * compatibility with broken comparators) using a system property.
+ * Cannot be a static boolean in the enclosing class due to
+ * circular dependencies. To be removed in a future release.
+ */
+ static final class LegacyMergeSort {
+ private static final boolean userRequested =
+ java.security.AccessController.doPrivileged(
+ new sun.security.action.GetBooleanAction(
+ "java.util.Arrays.useLegacyMergeSort")).booleanValue();
+ }
+
+ /*
+ * If this platform has an optimizing VM, check whether ComparableTimSort
+ * offers any performance benefit over TimSort in conjunction with a
+ * comparator that returns:
+ * {@code ((Comparable)first).compareTo(Second)}.
+ * If not, you are better off deleting ComparableTimSort to
+ * eliminate the code duplication. In other words, the commented
+ * out code below is the preferable implementation for sorting
+ * arrays of Comparables if it offers sufficient performance.
+ */
+
+// /**
+// * A comparator that implements the natural ordering of a group of
+// * mutually comparable elements. Using this comparator saves us
+// * from duplicating most of the code in this file (one version for
+// * Comparables, one for explicit Comparators).
+// */
+// private static final Comparator NATURAL_ORDER =
+// new Comparator() {
+// @SuppressWarnings("unchecked")
+// public int compare(Object first, Object second) {
+// return ((Comparable)first).compareTo(second);
+// }
+// };
+//
+// public static void sort(Object[] a) {
+// sort(a, 0, a.length, NATURAL_ORDER);
+// }
+//
+// public static void sort(Object[] a, int fromIndex, int toIndex) {
+// sort(a, fromIndex, toIndex, NATURAL_ORDER);
+// }
+
+ /**
+ * Sorts the specified array of objects into ascending order, according
+ * to the {@linkplain Comparable natural ordering} of its elements.
+ * All elements in the array must implement the {@link Comparable}
+ * interface. Furthermore, all elements in the array must be
+ * mutually comparable (that is, {@code e1.compareTo(e2)} must
+ * not throw a {@code ClassCastException} for any elements {@code e1}
+ * and {@code e2} in the array).
+ *
+ * This sort is guaranteed to be stable : equal elements will
+ * not be reordered as a result of the sort.
+ *
+ *
Implementation note: This implementation is a stable, adaptive,
+ * iterative mergesort that requires far fewer than n lg(n) comparisons
+ * when the input array is partially sorted, while offering the
+ * performance of a traditional mergesort when the input array is
+ * randomly ordered. If the input array is nearly sorted, the
+ * implementation requires approximately n comparisons. Temporary
+ * storage requirements vary from a small constant for nearly sorted
+ * input arrays to n/2 object references for randomly ordered input
+ * arrays.
*
- * This sort is guaranteed to be stable : equal elements will
- * not be reordered as a result of the sort.
+ *
The implementation takes equal advantage of ascending and
+ * descending order in its input array, and can take advantage of
+ * ascending and descending order in different parts of the the same
+ * input array. It is well-suited to merging two or more sorted arrays:
+ * simply concatenate the arrays and sort the resulting array.
*
- * The sorting algorithm is a modified mergesort (in which the merge is
- * omitted if the highest element in the low sublist is less than the
- * lowest element in the high sublist). This algorithm offers guaranteed
- * n*log(n) performance.
+ *
The implementation was adapted from Tim Peters's list sort for Python
+ * (
+ * TimSort ). It uses techiques from Peter McIlroy's "Optimistic
+ * Sorting and Information Theoretic Complexity", in Proceedings of the
+ * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474,
+ * January 1993.
*
* @param a the array to be sorted
- * @throws ClassCastException if the array contains elements that are not
- * mutually comparable (for example, strings and integers).
+ * @throws ClassCastException if the array contains elements that are not
+ * mutually comparable (for example, strings and integers)
+ * @throws IllegalArgumentException (optional) if the natural
+ * ordering of the array elements is found to violate the
+ * {@link Comparable} contract
*/
public static void sort(Object[] a) {
+ if (LegacyMergeSort.userRequested)
+ legacyMergeSort(a);
+ else
+ ComparableTimSort.sort(a);
+ }
+
+ /** To be removed in a future release. */
+ private static void legacyMergeSort(Object[] a) {
Object[] aux = a.clone();
mergeSort(aux, a, 0, a.length, 0);
}
@@ -1097,34 +1171,63 @@ public class Arrays {
* ascending order, according to the
* {@linkplain Comparable natural ordering} of its
* elements. The range to be sorted extends from index
- * fromIndex , inclusive, to index toIndex , exclusive.
- * (If fromIndex==toIndex , the range to be sorted is empty.) All
+ * {@code fromIndex}, inclusive, to index {@code toIndex}, exclusive.
+ * (If {@code fromIndex==toIndex}, the range to be sorted is empty.) All
* elements in this range must implement the {@link Comparable}
* interface. Furthermore, all elements in this range must be mutually
- * comparable (that is, e1.compareTo(e2) must not throw a
- * ClassCastException for any elements e1 and
- * e2 in the array).
+ * comparable (that is, {@code e1.compareTo(e2)} must not throw a
+ * {@code ClassCastException} for any elements {@code e1} and
+ * {@code e2} in the array).
+ *
+ *
This sort is guaranteed to be stable : equal elements will
+ * not be reordered as a result of the sort.
+ *
+ *
Implementation note: This implementation is a stable, adaptive,
+ * iterative mergesort that requires far fewer than n lg(n) comparisons
+ * when the input array is partially sorted, while offering the
+ * performance of a traditional mergesort when the input array is
+ * randomly ordered. If the input array is nearly sorted, the
+ * implementation requires approximately n comparisons. Temporary
+ * storage requirements vary from a small constant for nearly sorted
+ * input arrays to n/2 object references for randomly ordered input
+ * arrays.
*
- * This sort is guaranteed to be stable : equal elements will
- * not be reordered as a result of the sort.
+ *
The implementation takes equal advantage of ascending and
+ * descending order in its input array, and can take advantage of
+ * ascending and descending order in different parts of the the same
+ * input array. It is well-suited to merging two or more sorted arrays:
+ * simply concatenate the arrays and sort the resulting array.
*
- * The sorting algorithm is a modified mergesort (in which the merge is
- * omitted if the highest element in the low sublist is less than the
- * lowest element in the high sublist). This algorithm offers guaranteed
- * n*log(n) performance.
+ *
The implementation was adapted from Tim Peters's list sort for Python
+ * (
+ * TimSort ). It uses techiques from Peter McIlroy's "Optimistic
+ * Sorting and Information Theoretic Complexity", in Proceedings of the
+ * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474,
+ * January 1993.
*
* @param a the array to be sorted
* @param fromIndex the index of the first element (inclusive) to be
* sorted
* @param toIndex the index of the last element (exclusive) to be sorted
- * @throws IllegalArgumentException if fromIndex > toIndex
- * @throws ArrayIndexOutOfBoundsException if fromIndex < 0 or
- * toIndex > a.length
- * @throws ClassCastException if the array contains elements that are
- * not mutually comparable (for example, strings and
- * integers).
+ * @throws IllegalArgumentException if {@code fromIndex > toIndex} or
+ * (optional) if the natural ordering of the array elements is
+ * found to violate the {@link Comparable} contract
+ * @throws ArrayIndexOutOfBoundsException if {@code fromIndex < 0} or
+ * {@code toIndex > a.length}
+ * @throws ClassCastException if the array contains elements that are
+ * not mutually comparable (for example, strings and
+ * integers).
*/
public static void sort(Object[] a, int fromIndex, int toIndex) {
+ if (LegacyMergeSort.userRequested)
+ legacyMergeSort(a, fromIndex, toIndex);
+ else
+ ComparableTimSort.sort(a, fromIndex, toIndex);
+ }
+
+ /** To be removed in a future release. */
+ private static void legacyMergeSort(Object[] a,
+ int fromIndex, int toIndex) {
rangeCheck(a.length, fromIndex, toIndex);
Object[] aux = copyOfRange(a, fromIndex, toIndex);
mergeSort(aux, a, fromIndex, toIndex, -fromIndex);
@@ -1133,6 +1236,7 @@ public class Arrays {
/**
* Tuning parameter: list size at or below which insertion sort will be
* used in preference to mergesort or quicksort.
+ * To be removed in a future release.
*/
private static final int INSERTIONSORT_THRESHOLD = 7;
@@ -1142,6 +1246,7 @@ public class Arrays {
* low is the index in dest to start sorting
* high is the end index in dest to end sorting
* off is the offset to generate corresponding low, high in src
+ * To be removed in a future release.
*/
private static void mergeSort(Object[] src,
Object[] dest,
@@ -1197,25 +1302,53 @@ public class Arrays {
* Sorts the specified array of objects according to the order induced by
* the specified comparator. All elements in the array must be
* mutually comparable by the specified comparator (that is,
- * c.compare(e1, e2) must not throw a ClassCastException
- * for any elements e1 and e2 in the array).
+ * {@code c.compare(e1, e2)} must not throw a {@code ClassCastException}
+ * for any elements {@code e1} and {@code e2} in the array).
+ *
+ *
This sort is guaranteed to be stable : equal elements will
+ * not be reordered as a result of the sort.
+ *
+ *
Implementation note: This implementation is a stable, adaptive,
+ * iterative mergesort that requires far fewer than n lg(n) comparisons
+ * when the input array is partially sorted, while offering the
+ * performance of a traditional mergesort when the input array is
+ * randomly ordered. If the input array is nearly sorted, the
+ * implementation requires approximately n comparisons. Temporary
+ * storage requirements vary from a small constant for nearly sorted
+ * input arrays to n/2 object references for randomly ordered input
+ * arrays.
*
- * This sort is guaranteed to be stable : equal elements will
- * not be reordered as a result of the sort.
+ *
The implementation takes equal advantage of ascending and
+ * descending order in its input array, and can take advantage of
+ * ascending and descending order in different parts of the the same
+ * input array. It is well-suited to merging two or more sorted arrays:
+ * simply concatenate the arrays and sort the resulting array.
*
- * The sorting algorithm is a modified mergesort (in which the merge is
- * omitted if the highest element in the low sublist is less than the
- * lowest element in the high sublist). This algorithm offers guaranteed
- * n*log(n) performance.
+ *
The implementation was adapted from Tim Peters's list sort for Python
+ * (
+ * TimSort ). It uses techiques from Peter McIlroy's "Optimistic
+ * Sorting and Information Theoretic Complexity", in Proceedings of the
+ * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474,
+ * January 1993.
*
* @param a the array to be sorted
* @param c the comparator to determine the order of the array. A
- * null value indicates that the elements'
+ * {@code null} value indicates that the elements'
* {@linkplain Comparable natural ordering} should be used.
- * @throws ClassCastException if the array contains elements that are
- * not mutually comparable using the specified comparator.
+ * @throws ClassCastException if the array contains elements that are
+ * not mutually comparable using the specified comparator
+ * @throws IllegalArgumentException (optional) if the comparator is
+ * found to violate the {@link Comparator} contract
*/
public static void sort(T[] a, Comparator super T> c) {
+ if (LegacyMergeSort.userRequested)
+ legacyMergeSort(a, c);
+ else
+ TimSort.sort(a, c);
+ }
+
+ /** To be removed in a future release. */
+ private static void legacyMergeSort(T[] a, Comparator super T> c) {
T[] aux = a.clone();
if (c==null)
mergeSort(aux, a, 0, a.length, 0);
@@ -1226,36 +1359,65 @@ public class Arrays {
/**
* Sorts the specified range of the specified array of objects according
* to the order induced by the specified comparator. The range to be
- * sorted extends from index fromIndex , inclusive, to index
- * toIndex , exclusive. (If fromIndex==toIndex , the
+ * sorted extends from index {@code fromIndex}, inclusive, to index
+ * {@code toIndex}, exclusive. (If {@code fromIndex==toIndex}, the
* range to be sorted is empty.) All elements in the range must be
* mutually comparable by the specified comparator (that is,
- * c.compare(e1, e2) must not throw a ClassCastException
- * for any elements e1 and e2 in the range).
+ * {@code c.compare(e1, e2)} must not throw a {@code ClassCastException}
+ * for any elements {@code e1} and {@code e2} in the range).
+ *
+ *
This sort is guaranteed to be stable : equal elements will
+ * not be reordered as a result of the sort.
+ *
+ *
Implementation note: This implementation is a stable, adaptive,
+ * iterative mergesort that requires far fewer than n lg(n) comparisons
+ * when the input array is partially sorted, while offering the
+ * performance of a traditional mergesort when the input array is
+ * randomly ordered. If the input array is nearly sorted, the
+ * implementation requires approximately n comparisons. Temporary
+ * storage requirements vary from a small constant for nearly sorted
+ * input arrays to n/2 object references for randomly ordered input
+ * arrays.
*
- * This sort is guaranteed to be stable : equal elements will
- * not be reordered as a result of the sort.
+ *
The implementation takes equal advantage of ascending and
+ * descending order in its input array, and can take advantage of
+ * ascending and descending order in different parts of the the same
+ * input array. It is well-suited to merging two or more sorted arrays:
+ * simply concatenate the arrays and sort the resulting array.
*
- * The sorting algorithm is a modified mergesort (in which the merge is
- * omitted if the highest element in the low sublist is less than the
- * lowest element in the high sublist). This algorithm offers guaranteed
- * n*log(n) performance.
+ *
The implementation was adapted from Tim Peters's list sort for Python
+ * (
+ * TimSort ). It uses techiques from Peter McIlroy's "Optimistic
+ * Sorting and Information Theoretic Complexity", in Proceedings of the
+ * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474,
+ * January 1993.
*
* @param a the array to be sorted
* @param fromIndex the index of the first element (inclusive) to be
* sorted
* @param toIndex the index of the last element (exclusive) to be sorted
* @param c the comparator to determine the order of the array. A
- * null value indicates that the elements'
+ * {@code null} value indicates that the elements'
* {@linkplain Comparable natural ordering} should be used.
* @throws ClassCastException if the array contains elements that are not
* mutually comparable using the specified comparator.
- * @throws IllegalArgumentException if fromIndex > toIndex
- * @throws ArrayIndexOutOfBoundsException if fromIndex < 0 or
- * toIndex > a.length
+ * @throws IllegalArgumentException if {@code fromIndex > toIndex} or
+ * (optional) if the comparator is found to violate the
+ * {@link Comparator} contract
+ * @throws ArrayIndexOutOfBoundsException if {@code fromIndex < 0} or
+ * {@code toIndex > a.length}
*/
public static void sort(T[] a, int fromIndex, int toIndex,
Comparator super T> c) {
+ if (LegacyMergeSort.userRequested)
+ legacyMergeSort(a, fromIndex, toIndex, c);
+ else
+ TimSort.sort(a, fromIndex, toIndex, c);
+ }
+
+ /** To be removed in a future release. */
+ private static void legacyMergeSort(T[] a, int fromIndex, int toIndex,
+ Comparator super T> c) {
rangeCheck(a.length, fromIndex, toIndex);
T[] aux = copyOfRange(a, fromIndex, toIndex);
if (c==null)
@@ -1270,6 +1432,7 @@ public class Arrays {
* low is the index in dest to start sorting
* high is the end index in dest to end sorting
* off is the offset into src corresponding to low in dest
+ * To be removed in a future release.
*/
private static void mergeSort(Object[] src,
Object[] dest,
diff --git a/src/share/classes/java/util/Collections.java b/src/share/classes/java/util/Collections.java
index caec3ffd11c4216c8f1e012dccb639258f8a34ac..8597888dfa5d59cf00728999b655938e243c1da8 100644
--- a/src/share/classes/java/util/Collections.java
+++ b/src/share/classes/java/util/Collections.java
@@ -100,23 +100,42 @@ public class Collections {
/**
* Sorts the specified list into ascending order, according to the
- * natural ordering of its elements. All elements in the list must
- * implement the Comparable interface. Furthermore, all elements
- * in the list must be mutually comparable (that is,
- * e1.compareTo(e2) must not throw a ClassCastException
- * for any elements e1 and e2 in the list).
- *
- * This sort is guaranteed to be stable : equal elements will
- * not be reordered as a result of the sort.
- *
- * The specified list must be modifiable, but need not be resizable.
- *
- * The sorting algorithm is a modified mergesort (in which the merge is
- * omitted if the highest element in the low sublist is less than the
- * lowest element in the high sublist). This algorithm offers guaranteed
- * n log(n) performance.
- *
- * This implementation dumps the specified list into an array, sorts
+ * {@linkplain Comparable natural ordering} of its elements.
+ * All elements in the list must implement the {@link Comparable}
+ * interface. Furthermore, all elements in the list must be
+ * mutually comparable (that is, {@code e1.compareTo(e2)}
+ * must not throw a {@code ClassCastException} for any elements
+ * {@code e1} and {@code e2} in the list).
+ *
+ *
This sort is guaranteed to be stable : equal elements will
+ * not be reordered as a result of the sort.
+ *
+ *
The specified list must be modifiable, but need not be resizable.
+ *
+ *
Implementation note: This implementation is a stable, adaptive,
+ * iterative mergesort that requires far fewer than n lg(n) comparisons
+ * when the input array is partially sorted, while offering the
+ * performance of a traditional mergesort when the input array is
+ * randomly ordered. If the input array is nearly sorted, the
+ * implementation requires approximately n comparisons. Temporary
+ * storage requirements vary from a small constant for nearly sorted
+ * input arrays to n/2 object references for randomly ordered input
+ * arrays.
+ *
+ *
The implementation takes equal advantage of ascending and
+ * descending order in its input array, and can take advantage of
+ * ascending and descending order in different parts of the the same
+ * input array. It is well-suited to merging two or more sorted arrays:
+ * simply concatenate the arrays and sort the resulting array.
+ *
+ *
The implementation was adapted from Tim Peters's list sort for Python
+ * (
+ * TimSort ). It uses techiques from Peter McIlroy's "Optimistic
+ * Sorting and Information Theoretic Complexity", in Proceedings of the
+ * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474,
+ * January 1993.
+ *
+ *
This implementation dumps the specified list into an array, sorts
* the array, and iterates over the list resetting each element
* from the corresponding position in the array. This avoids the
* n2 log(n) performance that would result from attempting
@@ -126,8 +145,10 @@ public class Collections {
* @throws ClassCastException if the list contains elements that are not
* mutually comparable (for example, strings and integers).
* @throws UnsupportedOperationException if the specified list's
- * list-iterator does not support the set operation.
- * @see Comparable
+ * list-iterator does not support the {@code set} operation.
+ * @throws IllegalArgumentException (optional) if the implementation
+ * detects that the natural ordering of the list elements is
+ * found to violate the {@link Comparable} contract
*/
public static > void sort(List list) {
Object[] a = list.toArray();
@@ -143,19 +164,38 @@ public class Collections {
* Sorts the specified list according to the order induced by the
* specified comparator. All elements in the list must be mutually
* comparable using the specified comparator (that is,
- * c.compare(e1, e2) must not throw a ClassCastException
- * for any elements e1 and e2 in the list).
- *
- * This sort is guaranteed to be stable : equal elements will
- * not be reordered as a result of the sort.
- *
- * The sorting algorithm is a modified mergesort (in which the merge is
- * omitted if the highest element in the low sublist is less than the
- * lowest element in the high sublist). This algorithm offers guaranteed
- * n log(n) performance.
- *
- * The specified list must be modifiable, but need not be resizable.
- * This implementation dumps the specified list into an array, sorts
+ * {@code c.compare(e1, e2)} must not throw a {@code ClassCastException}
+ * for any elements {@code e1} and {@code e2} in the list).
+ *
+ *
This sort is guaranteed to be stable : equal elements will
+ * not be reordered as a result of the sort.
+ *
+ *
The specified list must be modifiable, but need not be resizable.
+ *
+ *
Implementation note: This implementation is a stable, adaptive,
+ * iterative mergesort that requires far fewer than n lg(n) comparisons
+ * when the input array is partially sorted, while offering the
+ * performance of a traditional mergesort when the input array is
+ * randomly ordered. If the input array is nearly sorted, the
+ * implementation requires approximately n comparisons. Temporary
+ * storage requirements vary from a small constant for nearly sorted
+ * input arrays to n/2 object references for randomly ordered input
+ * arrays.
+ *
+ *
The implementation takes equal advantage of ascending and
+ * descending order in its input array, and can take advantage of
+ * ascending and descending order in different parts of the the same
+ * input array. It is well-suited to merging two or more sorted arrays:
+ * simply concatenate the arrays and sort the resulting array.
+ *
+ *
The implementation was adapted from Tim Peters's list sort for Python
+ * (
+ * TimSort ). It uses techiques from Peter McIlroy's "Optimistic
+ * Sorting and Information Theoretic Complexity", in Proceedings of the
+ * Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474,
+ * January 1993.
+ *
+ *
This implementation dumps the specified list into an array, sorts
* the array, and iterates over the list resetting each element
* from the corresponding position in the array. This avoids the
* n2 log(n) performance that would result from attempting
@@ -163,13 +203,14 @@ public class Collections {
*
* @param list the list to be sorted.
* @param c the comparator to determine the order of the list. A
- * null value indicates that the elements' natural
+ * {@code null} value indicates that the elements' natural
* ordering should be used.
* @throws ClassCastException if the list contains elements that are not
* mutually comparable using the specified comparator.
* @throws UnsupportedOperationException if the specified list's
- * list-iterator does not support the set operation.
- * @see Comparator
+ * list-iterator does not support the {@code set} operation.
+ * @throws IllegalArgumentException (optional) if the comparator is
+ * found to violate the {@link Comparator} contract
*/
public static void sort(List list, Comparator super T> c) {
Object[] a = list.toArray();
diff --git a/src/share/classes/java/util/ComparableTimSort.java b/src/share/classes/java/util/ComparableTimSort.java
new file mode 100644
index 0000000000000000000000000000000000000000..750a89bebaa7fe8812159c4da84dd84c7a42c407
--- /dev/null
+++ b/src/share/classes/java/util/ComparableTimSort.java
@@ -0,0 +1,895 @@
+/*
+ * Copyright 2009 Google Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.util;
+
+/**
+ * This is a near duplicate of {@link TimSort}, modified for use with
+ * arrays of objects that implement {@link Comparable}, instead of using
+ * explicit comparators.
+ *
+ * If you are using an optimizing VM, you may find that ComparableTimSort
+ * offers no performance benefit over TimSort in conjunction with a
+ * comparator that simply returns {@code ((Comparable)first).compareTo(Second)}.
+ * If this is the case, you are better off deleting ComparableTimSort to
+ * eliminate the code duplication. (See Arrays.java for details.)
+ *
+ * @author Josh Bloch
+ */
+class ComparableTimSort {
+ /**
+ * This is the minimum sized sequence that will be merged. Shorter
+ * sequences will be lengthened by calling binarySort. If the entire
+ * array is less than this length, no merges will be performed.
+ *
+ * This constant should be a power of two. It was 64 in Tim Peter's C
+ * implementation, but 32 was empirically determined to work better in
+ * this implementation. In the unlikely event that you set this constant
+ * to be a number that's not a power of two, you'll need to change the
+ * {@link #minRunLength} computation.
+ *
+ * If you decrease this constant, you must change the stackLen
+ * computation in the TimSort constructor, or you risk an
+ * ArrayOutOfBounds exception. See listsort.txt for a discussion
+ * of the minimum stack length required as a function of the length
+ * of the array being sorted and the minimum merge sequence length.
+ */
+ private static final int MIN_MERGE = 32;
+
+ /**
+ * The array being sorted.
+ */
+ private final Object[] a;
+
+ /**
+ * When we get into galloping mode, we stay there until both runs win less
+ * often than MIN_GALLOP consecutive times.
+ */
+ private static final int MIN_GALLOP = 7;
+
+ /**
+ * This controls when we get *into* galloping mode. It is initialized
+ * to MIN_GALLOP. The mergeLo and mergeHi methods nudge it higher for
+ * random data, and lower for highly structured data.
+ */
+ private int minGallop = MIN_GALLOP;
+
+ /**
+ * Maximum initial size of tmp array, which is used for merging. The array
+ * can grow to accommodate demand.
+ *
+ * Unlike Tim's original C version, we do not allocate this much storage
+ * when sorting smaller arrays. This change was required for performance.
+ */
+ private static final int INITIAL_TMP_STORAGE_LENGTH = 256;
+
+ /**
+ * Temp storage for merges.
+ */
+ private Object[] tmp;
+
+ /**
+ * A stack of pending runs yet to be merged. Run i starts at
+ * address base[i] and extends for len[i] elements. It's always
+ * true (so long as the indices are in bounds) that:
+ *
+ * runBase[i] + runLen[i] == runBase[i + 1]
+ *
+ * so we could cut the storage for this, but it's a minor amount,
+ * and keeping all the info explicit simplifies the code.
+ */
+ private int stackSize = 0; // Number of pending runs on stack
+ private final int[] runBase;
+ private final int[] runLen;
+
+ /**
+ * Creates a TimSort instance to maintain the state of an ongoing sort.
+ *
+ * @param a the array to be sorted
+ */
+ private ComparableTimSort(Object[] a) {
+ this.a = a;
+
+ // Allocate temp storage (which may be increased later if necessary)
+ int len = a.length;
+ @SuppressWarnings({"unchecked", "UnnecessaryLocalVariable"})
+ Object[] newArray = new Object[len < 2 * INITIAL_TMP_STORAGE_LENGTH ?
+ len >>> 1 : INITIAL_TMP_STORAGE_LENGTH];
+ tmp = newArray;
+
+ /*
+ * Allocate runs-to-be-merged stack (which cannot be expanded). The
+ * stack length requirements are described in listsort.txt. The C
+ * version always uses the same stack length (85), but this was
+ * measured to be too expensive when sorting "mid-sized" arrays (e.g.,
+ * 100 elements) in Java. Therefore, we use smaller (but sufficiently
+ * large) stack lengths for smaller arrays. The "magic numbers" in the
+ * computation below must be changed if MIN_MERGE is decreased. See
+ * the MIN_MERGE declaration above for more information.
+ */
+ int stackLen = (len < 120 ? 5 :
+ len < 1542 ? 10 :
+ len < 119151 ? 19 : 40);
+ runBase = new int[stackLen];
+ runLen = new int[stackLen];
+ }
+
+ /*
+ * The next two methods (which are package private and static) constitute
+ * the entire API of this class. Each of these methods obeys the contract
+ * of the public method with the same signature in java.util.Arrays.
+ */
+
+ static void sort(Object[] a) {
+ sort(a, 0, a.length);
+ }
+
+ static void sort(Object[] a, int lo, int hi) {
+ rangeCheck(a.length, lo, hi);
+ int nRemaining = hi - lo;
+ if (nRemaining < 2)
+ return; // Arrays of size 0 and 1 are always sorted
+
+ // If array is small, do a "mini-TimSort" with no merges
+ if (nRemaining < MIN_MERGE) {
+ int initRunLen = countRunAndMakeAscending(a, lo, hi);
+ binarySort(a, lo, hi, lo + initRunLen);
+ return;
+ }
+
+ /**
+ * March over the array once, left to right, finding natural runs,
+ * extending short natural runs to minRun elements, and merging runs
+ * to maintain stack invariant.
+ */
+ ComparableTimSort ts = new ComparableTimSort(a);
+ int minRun = minRunLength(nRemaining);
+ do {
+ // Identify next run
+ int runLen = countRunAndMakeAscending(a, lo, hi);
+
+ // If run is short, extend to min(minRun, nRemaining)
+ if (runLen < minRun) {
+ int force = nRemaining <= minRun ? nRemaining : minRun;
+ binarySort(a, lo, lo + force, lo + runLen);
+ runLen = force;
+ }
+
+ // Push run onto pending-run stack, and maybe merge
+ ts.pushRun(lo, runLen);
+ ts.mergeCollapse();
+
+ // Advance to find next run
+ lo += runLen;
+ nRemaining -= runLen;
+ } while (nRemaining != 0);
+
+ // Merge all remaining runs to complete sort
+ assert lo == hi;
+ ts.mergeForceCollapse();
+ assert ts.stackSize == 1;
+ }
+
+ /**
+ * Sorts the specified portion of the specified array using a binary
+ * insertion sort. This is the best method for sorting small numbers
+ * of elements. It requires O(n log n) compares, but O(n^2) data
+ * movement (worst case).
+ *
+ * If the initial part of the specified range is already sorted,
+ * this method can take advantage of it: the method assumes that the
+ * elements from index {@code lo}, inclusive, to {@code start},
+ * exclusive are already sorted.
+ *
+ * @param a the array in which a range is to be sorted
+ * @param lo the index of the first element in the range to be sorted
+ * @param hi the index after the last element in the range to be sorted
+ * @param start the index of the first element in the range that is
+ * not already known to be sorted (@code lo <= start <= hi}
+ */
+ @SuppressWarnings("fallthrough")
+ private static void binarySort(Object[] a, int lo, int hi, int start) {
+ assert lo <= start && start <= hi;
+ if (start == lo)
+ start++;
+ for ( ; start < hi; start++) {
+ @SuppressWarnings("unchecked")
+ Comparable pivot = (Comparable) a[start];
+
+ // Set left (and right) to the index where a[start] (pivot) belongs
+ int left = lo;
+ int right = start;
+ assert left <= right;
+ /*
+ * Invariants:
+ * pivot >= all in [lo, left).
+ * pivot < all in [right, start).
+ */
+ while (left < right) {
+ int mid = (left + right) >>> 1;
+ if (pivot.compareTo(a[mid]) < 0)
+ right = mid;
+ else
+ left = mid + 1;
+ }
+ assert left == right;
+
+ /*
+ * The invariants still hold: pivot >= all in [lo, left) and
+ * pivot < all in [left, start), so pivot belongs at left. Note
+ * that if there are elements equal to pivot, left points to the
+ * first slot after them -- that's why this sort is stable.
+ * Slide elements over to make room to make room for pivot.
+ */
+ int n = start - left; // The number of elements to move
+ // Switch is just an optimization for arraycopy in default case
+ switch(n) {
+ case 2: a[left + 2] = a[left + 1];
+ case 1: a[left + 1] = a[left];
+ break;
+ default: System.arraycopy(a, left, a, left + 1, n);
+ }
+ a[left] = pivot;
+ }
+ }
+
+ /**
+ * Returns the length of the run beginning at the specified position in
+ * the specified array and reverses the run if it is descending (ensuring
+ * that the run will always be ascending when the method returns).
+ *
+ * A run is the longest ascending sequence with:
+ *
+ * a[lo] <= a[lo + 1] <= a[lo + 2] <= ...
+ *
+ * or the longest descending sequence with:
+ *
+ * a[lo] > a[lo + 1] > a[lo + 2] > ...
+ *
+ * For its intended use in a stable mergesort, the strictness of the
+ * definition of "descending" is needed so that the call can safely
+ * reverse a descending sequence without violating stability.
+ *
+ * @param a the array in which a run is to be counted and possibly reversed
+ * @param lo index of the first element in the run
+ * @param hi index after the last element that may be contained in the run.
+ It is required that @code{lo < hi}.
+ * @return the length of the run beginning at the specified position in
+ * the specified array
+ */
+ @SuppressWarnings("unchecked")
+ private static int countRunAndMakeAscending(Object[] a, int lo, int hi) {
+ assert lo < hi;
+ int runHi = lo + 1;
+ if (runHi == hi)
+ return 1;
+
+ // Find end of run, and reverse range if descending
+ if (((Comparable) a[runHi++]).compareTo(a[lo]) < 0) { // Descending
+ while(runHi < hi && ((Comparable) a[runHi]).compareTo(a[runHi - 1]) < 0)
+ runHi++;
+ reverseRange(a, lo, runHi);
+ } else { // Ascending
+ while (runHi < hi && ((Comparable) a[runHi]).compareTo(a[runHi - 1]) >= 0)
+ runHi++;
+ }
+
+ return runHi - lo;
+ }
+
+ /**
+ * Reverse the specified range of the specified array.
+ *
+ * @param a the array in which a range is to be reversed
+ * @param lo the index of the first element in the range to be reversed
+ * @param hi the index after the last element in the range to be reversed
+ */
+ private static void reverseRange(Object[] a, int lo, int hi) {
+ hi--;
+ while (lo < hi) {
+ Object t = a[lo];
+ a[lo++] = a[hi];
+ a[hi--] = t;
+ }
+ }
+
+ /**
+ * Returns the minimum acceptable run length for an array of the specified
+ * length. Natural runs shorter than this will be extended with
+ * {@link #binarySort}.
+ *
+ * Roughly speaking, the computation is:
+ *
+ * If n < MIN_MERGE, return n (it's too small to bother with fancy stuff).
+ * Else if n is an exact power of 2, return MIN_MERGE/2.
+ * Else return an int k, MIN_MERGE/2 <= k <= MIN_MERGE, such that n/k
+ * is close to, but strictly less than, an exact power of 2.
+ *
+ * For the rationale, see listsort.txt.
+ *
+ * @param n the length of the array to be sorted
+ * @return the length of the minimum run to be merged
+ */
+ private static int minRunLength(int n) {
+ assert n >= 0;
+ int r = 0; // Becomes 1 if any 1 bits are shifted off
+ while (n >= MIN_MERGE) {
+ r |= (n & 1);
+ n >>= 1;
+ }
+ return n + r;
+ }
+
+ /**
+ * Pushes the specified run onto the pending-run stack.
+ *
+ * @param runBase index of the first element in the run
+ * @param runLen the number of elements in the run
+ */
+ private void pushRun(int runBase, int runLen) {
+ this.runBase[stackSize] = runBase;
+ this.runLen[stackSize] = runLen;
+ stackSize++;
+ }
+
+ /**
+ * Examines the stack of runs waiting to be merged and merges adjacent runs
+ * until the stack invariants are reestablished:
+ *
+ * 1. runLen[i - 3] > runLen[i - 2] + runLen[i - 1]
+ * 2. runLen[i - 2] > runLen[i - 1]
+ *
+ * This method is called each time a new run is pushed onto the stack,
+ * so the invariants are guaranteed to hold for i < stackSize upon
+ * entry to the method.
+ */
+ private void mergeCollapse() {
+ while (stackSize > 1) {
+ int n = stackSize - 2;
+ if (n > 0 && runLen[n-1] <= runLen[n] + runLen[n+1]) {
+ if (runLen[n - 1] < runLen[n + 1])
+ n--;
+ mergeAt(n);
+ } else if (runLen[n] <= runLen[n + 1]) {
+ mergeAt(n);
+ } else {
+ break; // Invariant is established
+ }
+ }
+ }
+
+ /**
+ * Merges all runs on the stack until only one remains. This method is
+ * called once, to complete the sort.
+ */
+ private void mergeForceCollapse() {
+ while (stackSize > 1) {
+ int n = stackSize - 2;
+ if (n > 0 && runLen[n - 1] < runLen[n + 1])
+ n--;
+ mergeAt(n);
+ }
+ }
+
+ /**
+ * Merges the two runs at stack indices i and i+1. Run i must be
+ * the penultimate or antepenultimate run on the stack. In other words,
+ * i must be equal to stackSize-2 or stackSize-3.
+ *
+ * @param i stack index of the first of the two runs to merge
+ */
+ @SuppressWarnings("unchecked")
+ private void mergeAt(int i) {
+ assert stackSize >= 2;
+ assert i >= 0;
+ assert i == stackSize - 2 || i == stackSize - 3;
+
+ int base1 = runBase[i];
+ int len1 = runLen[i];
+ int base2 = runBase[i + 1];
+ int len2 = runLen[i + 1];
+ assert len1 > 0 && len2 > 0;
+ assert base1 + len1 == base2;
+
+ /*
+ * Record the length of the combined runs; if i is the 3rd-last
+ * run now, also slide over the last run (which isn't involved
+ * in this merge). The current run (i+1) goes away in any case.
+ */
+ runLen[i] = len1 + len2;
+ if (i == stackSize - 3) {
+ runBase[i + 1] = runBase[i + 2];
+ runLen[i + 1] = runLen[i + 2];
+ }
+ stackSize--;
+
+ /*
+ * Find where the first element of run2 goes in run1. Prior elements
+ * in run1 can be ignored (because they're already in place).
+ */
+ int k = gallopRight((Comparable) a[base2], a, base1, len1, 0);
+ assert k >= 0;
+ base1 += k;
+ len1 -= k;
+ if (len1 == 0)
+ return;
+
+ /*
+ * Find where the last element of run1 goes in run2. Subsequent elements
+ * in run2 can be ignored (because they're already in place).
+ */
+ len2 = gallopLeft((Comparable) a[base1 + len1 - 1], a,
+ base2, len2, len2 - 1);
+ assert len2 >= 0;
+ if (len2 == 0)
+ return;
+
+ // Merge remaining runs, using tmp array with min(len1, len2) elements
+ if (len1 <= len2)
+ mergeLo(base1, len1, base2, len2);
+ else
+ mergeHi(base1, len1, base2, len2);
+ }
+
+ /**
+ * Locates the position at which to insert the specified key into the
+ * specified sorted range; if the range contains an element equal to key,
+ * returns the index of the leftmost equal element.
+ *
+ * @param key the key whose insertion point to search for
+ * @param a the array in which to search
+ * @param base the index of the first element in the range
+ * @param len the length of the range; must be > 0
+ * @param hint the index at which to begin the search, 0 <= hint < n.
+ * The closer hint is to the result, the faster this method will run.
+ * @return the int k, 0 <= k <= n such that a[b + k - 1] < key <= a[b + k],
+ * pretending that a[b - 1] is minus infinity and a[b + n] is infinity.
+ * In other words, key belongs at index b + k; or in other words,
+ * the first k elements of a should precede key, and the last n - k
+ * should follow it.
+ */
+ private static int gallopLeft(Comparable key, Object[] a,
+ int base, int len, int hint) {
+ assert len > 0 && hint >= 0 && hint < len;
+
+ int lastOfs = 0;
+ int ofs = 1;
+ if (key.compareTo(a[base + hint]) > 0) {
+ // Gallop right until a[base+hint+lastOfs] < key <= a[base+hint+ofs]
+ int maxOfs = len - hint;
+ while (ofs < maxOfs && key.compareTo(a[base + hint + ofs]) > 0) {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if (ofs <= 0) // int overflow
+ ofs = maxOfs;
+ }
+ if (ofs > maxOfs)
+ ofs = maxOfs;
+
+ // Make offsets relative to base
+ lastOfs += hint;
+ ofs += hint;
+ } else { // key <= a[base + hint]
+ // Gallop left until a[base+hint-ofs] < key <= a[base+hint-lastOfs]
+ final int maxOfs = hint + 1;
+ while (ofs < maxOfs && key.compareTo(a[base + hint - ofs]) <= 0) {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if (ofs <= 0) // int overflow
+ ofs = maxOfs;
+ }
+ if (ofs > maxOfs)
+ ofs = maxOfs;
+
+ // Make offsets relative to base
+ int tmp = lastOfs;
+ lastOfs = hint - ofs;
+ ofs = hint - tmp;
+ }
+ assert -1 <= lastOfs && lastOfs < ofs && ofs <= len;
+
+ /*
+ * Now a[base+lastOfs] < key <= a[base+ofs], so key belongs somewhere
+ * to the right of lastOfs but no farther right than ofs. Do a binary
+ * search, with invariant a[base + lastOfs - 1] < key <= a[base + ofs].
+ */
+ lastOfs++;
+ while (lastOfs < ofs) {
+ int m = lastOfs + ((ofs - lastOfs) >>> 1);
+
+ if (key.compareTo(a[base + m]) > 0)
+ lastOfs = m + 1; // a[base + m] < key
+ else
+ ofs = m; // key <= a[base + m]
+ }
+ assert lastOfs == ofs; // so a[base + ofs - 1] < key <= a[base + ofs]
+ return ofs;
+ }
+
+ /**
+ * Like gallopLeft, except that if the range contains an element equal to
+ * key, gallopRight returns the index after the rightmost equal element.
+ *
+ * @param key the key whose insertion point to search for
+ * @param a the array in which to search
+ * @param base the index of the first element in the range
+ * @param len the length of the range; must be > 0
+ * @param hint the index at which to begin the search, 0 <= hint < n.
+ * The closer hint is to the result, the faster this method will run.
+ * @return the int k, 0 <= k <= n such that a[b + k - 1] <= key < a[b + k]
+ */
+ private static int gallopRight(Comparable key, Object[] a,
+ int base, int len, int hint) {
+ assert len > 0 && hint >= 0 && hint < len;
+
+ int ofs = 1;
+ int lastOfs = 0;
+ if (key.compareTo(a[base + hint]) < 0) {
+ // Gallop left until a[b+hint - ofs] <= key < a[b+hint - lastOfs]
+ int maxOfs = hint + 1;
+ while (ofs < maxOfs && key.compareTo(a[base + hint - ofs]) < 0) {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if (ofs <= 0) // int overflow
+ ofs = maxOfs;
+ }
+ if (ofs > maxOfs)
+ ofs = maxOfs;
+
+ // Make offsets relative to b
+ int tmp = lastOfs;
+ lastOfs = hint - ofs;
+ ofs = hint - tmp;
+ } else { // a[b + hint] <= key
+ // Gallop right until a[b+hint + lastOfs] <= key < a[b+hint + ofs]
+ int maxOfs = len - hint;
+ while (ofs < maxOfs && key.compareTo(a[base + hint + ofs]) >= 0) {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if (ofs <= 0) // int overflow
+ ofs = maxOfs;
+ }
+ if (ofs > maxOfs)
+ ofs = maxOfs;
+
+ // Make offsets relative to b
+ lastOfs += hint;
+ ofs += hint;
+ }
+ assert -1 <= lastOfs && lastOfs < ofs && ofs <= len;
+
+ /*
+ * Now a[b + lastOfs] <= key < a[b + ofs], so key belongs somewhere to
+ * the right of lastOfs but no farther right than ofs. Do a binary
+ * search, with invariant a[b + lastOfs - 1] <= key < a[b + ofs].
+ */
+ lastOfs++;
+ while (lastOfs < ofs) {
+ int m = lastOfs + ((ofs - lastOfs) >>> 1);
+
+ if (key.compareTo(a[base + m]) < 0)
+ ofs = m; // key < a[b + m]
+ else
+ lastOfs = m + 1; // a[b + m] <= key
+ }
+ assert lastOfs == ofs; // so a[b + ofs - 1] <= key < a[b + ofs]
+ return ofs;
+ }
+
+ /**
+ * Merges two adjacent runs in place, in a stable fashion. The first
+ * element of the first run must be greater than the first element of the
+ * second run (a[base1] > a[base2]), and the last element of the first run
+ * (a[base1 + len1-1]) must be greater than all elements of the second run.
+ *
+ * For performance, this method should be called only when len1 <= len2;
+ * its twin, mergeHi should be called if len1 >= len2. (Either method
+ * may be called if len1 == len2.)
+ *
+ * @param base1 index of first element in first run to be merged
+ * @param len1 length of first run to be merged (must be > 0)
+ * @param base2 index of first element in second run to be merged
+ * (must be aBase + aLen)
+ * @param len2 length of second run to be merged (must be > 0)
+ */
+ @SuppressWarnings("unchecked")
+ private void mergeLo(int base1, int len1, int base2, int len2) {
+ assert len1 > 0 && len2 > 0 && base1 + len1 == base2;
+
+ // Copy first run into temp array
+ Object[] a = this.a; // For performance
+ Object[] tmp = ensureCapacity(len1);
+ System.arraycopy(a, base1, tmp, 0, len1);
+
+ int cursor1 = 0; // Indexes into tmp array
+ int cursor2 = base2; // Indexes int a
+ int dest = base1; // Indexes int a
+
+ // Move first element of second run and deal with degenerate cases
+ a[dest++] = a[cursor2++];
+ if (--len2 == 0) {
+ System.arraycopy(tmp, cursor1, a, dest, len1);
+ return;
+ }
+ if (len1 == 1) {
+ System.arraycopy(a, cursor2, a, dest, len2);
+ a[dest + len2] = tmp[cursor1]; // Last elt of run 1 to end of merge
+ return;
+ }
+
+ int minGallop = this.minGallop; // Use local variable for performance
+ outer:
+ while (true) {
+ int count1 = 0; // Number of times in a row that first run won
+ int count2 = 0; // Number of times in a row that second run won
+
+ /*
+ * Do the straightforward thing until (if ever) one run starts
+ * winning consistently.
+ */
+ do {
+ assert len1 > 1 && len2 > 0;
+ if (((Comparable) a[cursor2]).compareTo(tmp[cursor1]) < 0) {
+ a[dest++] = a[cursor2++];
+ count2++;
+ count1 = 0;
+ if (--len2 == 0)
+ break outer;
+ } else {
+ a[dest++] = tmp[cursor1++];
+ count1++;
+ count2 = 0;
+ if (--len1 == 1)
+ break outer;
+ }
+ } while ((count1 | count2) < minGallop);
+
+ /*
+ * One run is winning so consistently that galloping may be a
+ * huge win. So try that, and continue galloping until (if ever)
+ * neither run appears to be winning consistently anymore.
+ */
+ do {
+ assert len1 > 1 && len2 > 0;
+ count1 = gallopRight((Comparable) a[cursor2], tmp, cursor1, len1, 0);
+ if (count1 != 0) {
+ System.arraycopy(tmp, cursor1, a, dest, count1);
+ dest += count1;
+ cursor1 += count1;
+ len1 -= count1;
+ if (len1 <= 1) // len1 == 1 || len1 == 0
+ break outer;
+ }
+ a[dest++] = a[cursor2++];
+ if (--len2 == 0)
+ break outer;
+
+ count2 = gallopLeft((Comparable) tmp[cursor1], a, cursor2, len2, 0);
+ if (count2 != 0) {
+ System.arraycopy(a, cursor2, a, dest, count2);
+ dest += count2;
+ cursor2 += count2;
+ len2 -= count2;
+ if (len2 == 0)
+ break outer;
+ }
+ a[dest++] = tmp[cursor1++];
+ if (--len1 == 1)
+ break outer;
+ minGallop--;
+ } while (count1 >= MIN_GALLOP | count2 >= MIN_GALLOP);
+ if (minGallop < 0)
+ minGallop = 0;
+ minGallop += 2; // Penalize for leaving gallop mode
+ } // End of "outer" loop
+ this.minGallop = minGallop < 1 ? 1 : minGallop; // Write back to field
+
+ if (len1 == 1) {
+ assert len2 > 0;
+ System.arraycopy(a, cursor2, a, dest, len2);
+ a[dest + len2] = tmp[cursor1]; // Last elt of run 1 to end of merge
+ } else if (len1 == 0) {
+ throw new IllegalArgumentException(
+ "Comparison method violates its general contract!");
+ } else {
+ assert len2 == 0;
+ assert len1 > 1;
+ System.arraycopy(tmp, cursor1, a, dest, len1);
+ }
+ }
+
+ /**
+ * Like mergeLo, except that this method should be called only if
+ * len1 >= len2; mergeLo should be called if len1 <= len2. (Either method
+ * may be called if len1 == len2.)
+ *
+ * @param base1 index of first element in first run to be merged
+ * @param len1 length of first run to be merged (must be > 0)
+ * @param base2 index of first element in second run to be merged
+ * (must be aBase + aLen)
+ * @param len2 length of second run to be merged (must be > 0)
+ */
+ @SuppressWarnings("unchecked")
+ private void mergeHi(int base1, int len1, int base2, int len2) {
+ assert len1 > 0 && len2 > 0 && base1 + len1 == base2;
+
+ // Copy second run into temp array
+ Object[] a = this.a; // For performance
+ Object[] tmp = ensureCapacity(len2);
+ System.arraycopy(a, base2, tmp, 0, len2);
+
+ int cursor1 = base1 + len1 - 1; // Indexes into a
+ int cursor2 = len2 - 1; // Indexes into tmp array
+ int dest = base2 + len2 - 1; // Indexes into a
+
+ // Move last element of first run and deal with degenerate cases
+ a[dest--] = a[cursor1--];
+ if (--len1 == 0) {
+ System.arraycopy(tmp, 0, a, dest - (len2 - 1), len2);
+ return;
+ }
+ if (len2 == 1) {
+ dest -= len1;
+ cursor1 -= len1;
+ System.arraycopy(a, cursor1 + 1, a, dest + 1, len1);
+ a[dest] = tmp[cursor2];
+ return;
+ }
+
+ int minGallop = this.minGallop; // Use local variable for performance
+ outer:
+ while (true) {
+ int count1 = 0; // Number of times in a row that first run won
+ int count2 = 0; // Number of times in a row that second run won
+
+ /*
+ * Do the straightforward thing until (if ever) one run
+ * appears to win consistently.
+ */
+ do {
+ assert len1 > 0 && len2 > 1;
+ if (((Comparable) tmp[cursor2]).compareTo(a[cursor1]) < 0) {
+ a[dest--] = a[cursor1--];
+ count1++;
+ count2 = 0;
+ if (--len1 == 0)
+ break outer;
+ } else {
+ a[dest--] = tmp[cursor2--];
+ count2++;
+ count1 = 0;
+ if (--len2 == 1)
+ break outer;
+ }
+ } while ((count1 | count2) < minGallop);
+
+ /*
+ * One run is winning so consistently that galloping may be a
+ * huge win. So try that, and continue galloping until (if ever)
+ * neither run appears to be winning consistently anymore.
+ */
+ do {
+ assert len1 > 0 && len2 > 1;
+ count1 = len1 - gallopRight((Comparable) tmp[cursor2], a, base1, len1, len1 - 1);
+ if (count1 != 0) {
+ dest -= count1;
+ cursor1 -= count1;
+ len1 -= count1;
+ System.arraycopy(a, cursor1 + 1, a, dest + 1, count1);
+ if (len1 == 0)
+ break outer;
+ }
+ a[dest--] = tmp[cursor2--];
+ if (--len2 == 1)
+ break outer;
+
+ count2 = len2 - gallopLeft((Comparable) a[cursor1], tmp, 0, len2, len2 - 1);
+ if (count2 != 0) {
+ dest -= count2;
+ cursor2 -= count2;
+ len2 -= count2;
+ System.arraycopy(tmp, cursor2 + 1, a, dest + 1, count2);
+ if (len2 <= 1)
+ break outer; // len2 == 1 || len2 == 0
+ }
+ a[dest--] = a[cursor1--];
+ if (--len1 == 0)
+ break outer;
+ minGallop--;
+ } while (count1 >= MIN_GALLOP | count2 >= MIN_GALLOP);
+ if (minGallop < 0)
+ minGallop = 0;
+ minGallop += 2; // Penalize for leaving gallop mode
+ } // End of "outer" loop
+ this.minGallop = minGallop < 1 ? 1 : minGallop; // Write back to field
+
+ if (len2 == 1) {
+ assert len1 > 0;
+ dest -= len1;
+ cursor1 -= len1;
+ System.arraycopy(a, cursor1 + 1, a, dest + 1, len1);
+ a[dest] = tmp[cursor2]; // Move first elt of run2 to front of merge
+ } else if (len2 == 0) {
+ throw new IllegalArgumentException(
+ "Comparison method violates its general contract!");
+ } else {
+ assert len1 == 0;
+ assert len2 > 0;
+ System.arraycopy(tmp, 0, a, dest - (len2 - 1), len2);
+ }
+ }
+
+ /**
+ * Ensures that the external array tmp has at least the specified
+ * number of elements, increasing its size if necessary. The size
+ * increases exponentially to ensure amortized linear time complexity.
+ *
+ * @param minCapacity the minimum required capacity of the tmp array
+ * @return tmp, whether or not it grew
+ */
+ private Object[] ensureCapacity(int minCapacity) {
+ if (tmp.length < minCapacity) {
+ // Compute smallest power of 2 > minCapacity
+ int newSize = minCapacity;
+ newSize |= newSize >> 1;
+ newSize |= newSize >> 2;
+ newSize |= newSize >> 4;
+ newSize |= newSize >> 8;
+ newSize |= newSize >> 16;
+ newSize++;
+
+ if (newSize < 0) // Not bloody likely!
+ newSize = minCapacity;
+ else
+ newSize = Math.min(newSize, a.length >>> 1);
+
+ @SuppressWarnings({"unchecked", "UnnecessaryLocalVariable"})
+ Object[] newArray = new Object[newSize];
+ tmp = newArray;
+ }
+ return tmp;
+ }
+
+ /**
+ * Checks that fromIndex and toIndex are in range, and throws an
+ * appropriate exception if they aren't.
+ *
+ * @param arrayLen the length of the array
+ * @param fromIndex the index of the first element of the range
+ * @param toIndex the index after the last element of the range
+ * @throws IllegalArgumentException if fromIndex > toIndex
+ * @throws ArrayIndexOutOfBoundsException if fromIndex < 0
+ * or toIndex > arrayLen
+ */
+ private static void rangeCheck(int arrayLen, int fromIndex, int toIndex) {
+ if (fromIndex > toIndex)
+ throw new IllegalArgumentException("fromIndex(" + fromIndex +
+ ") > toIndex(" + toIndex+")");
+ if (fromIndex < 0)
+ throw new ArrayIndexOutOfBoundsException(fromIndex);
+ if (toIndex > arrayLen)
+ throw new ArrayIndexOutOfBoundsException(toIndex);
+ }
+}
diff --git a/src/share/classes/java/util/Formatter.java b/src/share/classes/java/util/Formatter.java
index eb49ec9c5dad8f1b1d19c5a9ac9da718ee0b1da8..027e36dcc81702f8de95e22e3c33cc44f06322aa 100644
--- a/src/share/classes/java/util/Formatter.java
+++ b/src/share/classes/java/util/Formatter.java
@@ -2818,15 +2818,18 @@ public final class Formatter implements Closeable, Flushable {
}
private void printString(Object arg, Locale l) throws IOException {
- if (arg == null) {
- print("null");
- } else if (arg instanceof Formattable) {
+ if (arg instanceof Formattable) {
Formatter fmt = formatter;
if (formatter.locale() != l)
fmt = new Formatter(formatter.out(), l);
((Formattable)arg).formatTo(fmt, f.valueOf(), width, precision);
} else {
- print(arg.toString());
+ if (f.contains(Flags.ALTERNATE))
+ failMismatch(Flags.ALTERNATE, 's');
+ if (arg == null)
+ print("null");
+ else
+ print(arg.toString());
}
}
diff --git a/src/share/classes/java/util/TimSort.java b/src/share/classes/java/util/TimSort.java
new file mode 100644
index 0000000000000000000000000000000000000000..1d4e710a49921eb98df02db182346602da5a6c11
--- /dev/null
+++ b/src/share/classes/java/util/TimSort.java
@@ -0,0 +1,928 @@
+/*
+ * Copyright 2009 Google Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.util;
+
+/**
+ * A stable, adaptive, iterative mergesort that requires far fewer than
+ * n lg(n) comparisons when running on partially sorted arrays, while
+ * offering performance comparable to a traditional mergesort when run
+ * on random arrays. Like all proper mergesorts, this sort is stable and
+ * runs O(n log n) time (worst case). In the worst case, this sort requires
+ * temporary storage space for n/2 object references; in the best case,
+ * it requires only a small constant amount of space.
+ *
+ * This implementation was adapted from Tim Peters's list sort for
+ * Python, which is described in detail here:
+ *
+ * http://svn.python.org/projects/python/trunk/Objects/listsort.txt
+ *
+ * Tim's C code may be found here:
+ *
+ * http://svn.python.org/projects/python/trunk/Objects/listobject.c
+ *
+ * The underlying techniques are described in this paper (and may have
+ * even earlier origins):
+ *
+ * "Optimistic Sorting and Information Theoretic Complexity"
+ * Peter McIlroy
+ * SODA (Fourth Annual ACM-SIAM Symposium on Discrete Algorithms),
+ * pp 467-474, Austin, Texas, 25-27 January 1993.
+ *
+ * While the API to this class consists solely of static methods, it is
+ * (privately) instantiable; a TimSort instance holds the state of an ongoing
+ * sort, assuming the input array is large enough to warrant the full-blown
+ * TimSort. Small arrays are sorted in place, using a binary insertion sort.
+ *
+ * @author Josh Bloch
+ */
+class TimSort {
+ /**
+ * This is the minimum sized sequence that will be merged. Shorter
+ * sequences will be lengthened by calling binarySort. If the entire
+ * array is less than this length, no merges will be performed.
+ *
+ * This constant should be a power of two. It was 64 in Tim Peter's C
+ * implementation, but 32 was empirically determined to work better in
+ * this implementation. In the unlikely event that you set this constant
+ * to be a number that's not a power of two, you'll need to change the
+ * {@link #minRunLength} computation.
+ *
+ * If you decrease this constant, you must change the stackLen
+ * computation in the TimSort constructor, or you risk an
+ * ArrayOutOfBounds exception. See listsort.txt for a discussion
+ * of the minimum stack length required as a function of the length
+ * of the array being sorted and the minimum merge sequence length.
+ */
+ private static final int MIN_MERGE = 32;
+
+ /**
+ * The array being sorted.
+ */
+ private final T[] a;
+
+ /**
+ * The comparator for this sort.
+ */
+ private final Comparator super T> c;
+
+ /**
+ * When we get into galloping mode, we stay there until both runs win less
+ * often than MIN_GALLOP consecutive times.
+ */
+ private static final int MIN_GALLOP = 7;
+
+ /**
+ * This controls when we get *into* galloping mode. It is initialized
+ * to MIN_GALLOP. The mergeLo and mergeHi methods nudge it higher for
+ * random data, and lower for highly structured data.
+ */
+ private int minGallop = MIN_GALLOP;
+
+ /**
+ * Maximum initial size of tmp array, which is used for merging. The array
+ * can grow to accommodate demand.
+ *
+ * Unlike Tim's original C version, we do not allocate this much storage
+ * when sorting smaller arrays. This change was required for performance.
+ */
+ private static final int INITIAL_TMP_STORAGE_LENGTH = 256;
+
+ /**
+ * Temp storage for merges.
+ */
+ private T[] tmp; // Actual runtime type will be Object[], regardless of T
+
+ /**
+ * A stack of pending runs yet to be merged. Run i starts at
+ * address base[i] and extends for len[i] elements. It's always
+ * true (so long as the indices are in bounds) that:
+ *
+ * runBase[i] + runLen[i] == runBase[i + 1]
+ *
+ * so we could cut the storage for this, but it's a minor amount,
+ * and keeping all the info explicit simplifies the code.
+ */
+ private int stackSize = 0; // Number of pending runs on stack
+ private final int[] runBase;
+ private final int[] runLen;
+
+ /**
+ * Creates a TimSort instance to maintain the state of an ongoing sort.
+ *
+ * @param a the array to be sorted
+ * @param c the comparator to determine the order of the sort
+ */
+ private TimSort(T[] a, Comparator super T> c) {
+ this.a = a;
+ this.c = c;
+
+ // Allocate temp storage (which may be increased later if necessary)
+ int len = a.length;
+ @SuppressWarnings({"unchecked", "UnnecessaryLocalVariable"})
+ T[] newArray = (T[]) new Object[len < 2 * INITIAL_TMP_STORAGE_LENGTH ?
+ len >>> 1 : INITIAL_TMP_STORAGE_LENGTH];
+ tmp = newArray;
+
+ /*
+ * Allocate runs-to-be-merged stack (which cannot be expanded). The
+ * stack length requirements are described in listsort.txt. The C
+ * version always uses the same stack length (85), but this was
+ * measured to be too expensive when sorting "mid-sized" arrays (e.g.,
+ * 100 elements) in Java. Therefore, we use smaller (but sufficiently
+ * large) stack lengths for smaller arrays. The "magic numbers" in the
+ * computation below must be changed if MIN_MERGE is decreased. See
+ * the MIN_MERGE declaration above for more information.
+ */
+ int stackLen = (len < 120 ? 5 :
+ len < 1542 ? 10 :
+ len < 119151 ? 19 : 40);
+ runBase = new int[stackLen];
+ runLen = new int[stackLen];
+ }
+
+ /*
+ * The next two methods (which are package private and static) constitute
+ * the entire API of this class. Each of these methods obeys the contract
+ * of the public method with the same signature in java.util.Arrays.
+ */
+
+ static void sort(T[] a, Comparator super T> c) {
+ sort(a, 0, a.length, c);
+ }
+
+ static void sort(T[] a, int lo, int hi, Comparator super T> c) {
+ if (c == null) {
+ Arrays.sort(a, lo, hi);
+ return;
+ }
+
+ rangeCheck(a.length, lo, hi);
+ int nRemaining = hi - lo;
+ if (nRemaining < 2)
+ return; // Arrays of size 0 and 1 are always sorted
+
+ // If array is small, do a "mini-TimSort" with no merges
+ if (nRemaining < MIN_MERGE) {
+ int initRunLen = countRunAndMakeAscending(a, lo, hi, c);
+ binarySort(a, lo, hi, lo + initRunLen, c);
+ return;
+ }
+
+ /**
+ * March over the array once, left to right, finding natural runs,
+ * extending short natural runs to minRun elements, and merging runs
+ * to maintain stack invariant.
+ */
+ TimSort ts = new TimSort(a, c);
+ int minRun = minRunLength(nRemaining);
+ do {
+ // Identify next run
+ int runLen = countRunAndMakeAscending(a, lo, hi, c);
+
+ // If run is short, extend to min(minRun, nRemaining)
+ if (runLen < minRun) {
+ int force = nRemaining <= minRun ? nRemaining : minRun;
+ binarySort(a, lo, lo + force, lo + runLen, c);
+ runLen = force;
+ }
+
+ // Push run onto pending-run stack, and maybe merge
+ ts.pushRun(lo, runLen);
+ ts.mergeCollapse();
+
+ // Advance to find next run
+ lo += runLen;
+ nRemaining -= runLen;
+ } while (nRemaining != 0);
+
+ // Merge all remaining runs to complete sort
+ assert lo == hi;
+ ts.mergeForceCollapse();
+ assert ts.stackSize == 1;
+ }
+
+ /**
+ * Sorts the specified portion of the specified array using a binary
+ * insertion sort. This is the best method for sorting small numbers
+ * of elements. It requires O(n log n) compares, but O(n^2) data
+ * movement (worst case).
+ *
+ * If the initial part of the specified range is already sorted,
+ * this method can take advantage of it: the method assumes that the
+ * elements from index {@code lo}, inclusive, to {@code start},
+ * exclusive are already sorted.
+ *
+ * @param a the array in which a range is to be sorted
+ * @param lo the index of the first element in the range to be sorted
+ * @param hi the index after the last element in the range to be sorted
+ * @param start the index of the first element in the range that is
+ * not already known to be sorted (@code lo <= start <= hi}
+ * @param c comparator to used for the sort
+ */
+ @SuppressWarnings("fallthrough")
+ private static void binarySort(T[] a, int lo, int hi, int start,
+ Comparator super T> c) {
+ assert lo <= start && start <= hi;
+ if (start == lo)
+ start++;
+ for ( ; start < hi; start++) {
+ T pivot = a[start];
+
+ // Set left (and right) to the index where a[start] (pivot) belongs
+ int left = lo;
+ int right = start;
+ assert left <= right;
+ /*
+ * Invariants:
+ * pivot >= all in [lo, left).
+ * pivot < all in [right, start).
+ */
+ while (left < right) {
+ int mid = (left + right) >>> 1;
+ if (c.compare(pivot, a[mid]) < 0)
+ right = mid;
+ else
+ left = mid + 1;
+ }
+ assert left == right;
+
+ /*
+ * The invariants still hold: pivot >= all in [lo, left) and
+ * pivot < all in [left, start), so pivot belongs at left. Note
+ * that if there are elements equal to pivot, left points to the
+ * first slot after them -- that's why this sort is stable.
+ * Slide elements over to make room to make room for pivot.
+ */
+ int n = start - left; // The number of elements to move
+ // Switch is just an optimization for arraycopy in default case
+ switch(n) {
+ case 2: a[left + 2] = a[left + 1];
+ case 1: a[left + 1] = a[left];
+ break;
+ default: System.arraycopy(a, left, a, left + 1, n);
+ }
+ a[left] = pivot;
+ }
+ }
+
+ /**
+ * Returns the length of the run beginning at the specified position in
+ * the specified array and reverses the run if it is descending (ensuring
+ * that the run will always be ascending when the method returns).
+ *
+ * A run is the longest ascending sequence with:
+ *
+ * a[lo] <= a[lo + 1] <= a[lo + 2] <= ...
+ *
+ * or the longest descending sequence with:
+ *
+ * a[lo] > a[lo + 1] > a[lo + 2] > ...
+ *
+ * For its intended use in a stable mergesort, the strictness of the
+ * definition of "descending" is needed so that the call can safely
+ * reverse a descending sequence without violating stability.
+ *
+ * @param a the array in which a run is to be counted and possibly reversed
+ * @param lo index of the first element in the run
+ * @param hi index after the last element that may be contained in the run.
+ It is required that @code{lo < hi}.
+ * @param c the comparator to used for the sort
+ * @return the length of the run beginning at the specified position in
+ * the specified array
+ */
+ private static int countRunAndMakeAscending(T[] a, int lo, int hi,
+ Comparator super T> c) {
+ assert lo < hi;
+ int runHi = lo + 1;
+ if (runHi == hi)
+ return 1;
+
+ // Find end of run, and reverse range if descending
+ if (c.compare(a[runHi++], a[lo]) < 0) { // Descending
+ while(runHi < hi && c.compare(a[runHi], a[runHi - 1]) < 0)
+ runHi++;
+ reverseRange(a, lo, runHi);
+ } else { // Ascending
+ while (runHi < hi && c.compare(a[runHi], a[runHi - 1]) >= 0)
+ runHi++;
+ }
+
+ return runHi - lo;
+ }
+
+ /**
+ * Reverse the specified range of the specified array.
+ *
+ * @param a the array in which a range is to be reversed
+ * @param lo the index of the first element in the range to be reversed
+ * @param hi the index after the last element in the range to be reversed
+ */
+ private static void reverseRange(Object[] a, int lo, int hi) {
+ hi--;
+ while (lo < hi) {
+ Object t = a[lo];
+ a[lo++] = a[hi];
+ a[hi--] = t;
+ }
+ }
+
+ /**
+ * Returns the minimum acceptable run length for an array of the specified
+ * length. Natural runs shorter than this will be extended with
+ * {@link #binarySort}.
+ *
+ * Roughly speaking, the computation is:
+ *
+ * If n < MIN_MERGE, return n (it's too small to bother with fancy stuff).
+ * Else if n is an exact power of 2, return MIN_MERGE/2.
+ * Else return an int k, MIN_MERGE/2 <= k <= MIN_MERGE, such that n/k
+ * is close to, but strictly less than, an exact power of 2.
+ *
+ * For the rationale, see listsort.txt.
+ *
+ * @param n the length of the array to be sorted
+ * @return the length of the minimum run to be merged
+ */
+ private static int minRunLength(int n) {
+ assert n >= 0;
+ int r = 0; // Becomes 1 if any 1 bits are shifted off
+ while (n >= MIN_MERGE) {
+ r |= (n & 1);
+ n >>= 1;
+ }
+ return n + r;
+ }
+
+ /**
+ * Pushes the specified run onto the pending-run stack.
+ *
+ * @param runBase index of the first element in the run
+ * @param runLen the number of elements in the run
+ */
+ private void pushRun(int runBase, int runLen) {
+ this.runBase[stackSize] = runBase;
+ this.runLen[stackSize] = runLen;
+ stackSize++;
+ }
+
+ /**
+ * Examines the stack of runs waiting to be merged and merges adjacent runs
+ * until the stack invariants are reestablished:
+ *
+ * 1. runLen[i - 3] > runLen[i - 2] + runLen[i - 1]
+ * 2. runLen[i - 2] > runLen[i - 1]
+ *
+ * This method is called each time a new run is pushed onto the stack,
+ * so the invariants are guaranteed to hold for i < stackSize upon
+ * entry to the method.
+ */
+ private void mergeCollapse() {
+ while (stackSize > 1) {
+ int n = stackSize - 2;
+ if (n > 0 && runLen[n-1] <= runLen[n] + runLen[n+1]) {
+ if (runLen[n - 1] < runLen[n + 1])
+ n--;
+ mergeAt(n);
+ } else if (runLen[n] <= runLen[n + 1]) {
+ mergeAt(n);
+ } else {
+ break; // Invariant is established
+ }
+ }
+ }
+
+ /**
+ * Merges all runs on the stack until only one remains. This method is
+ * called once, to complete the sort.
+ */
+ private void mergeForceCollapse() {
+ while (stackSize > 1) {
+ int n = stackSize - 2;
+ if (n > 0 && runLen[n - 1] < runLen[n + 1])
+ n--;
+ mergeAt(n);
+ }
+ }
+
+ /**
+ * Merges the two runs at stack indices i and i+1. Run i must be
+ * the penultimate or antepenultimate run on the stack. In other words,
+ * i must be equal to stackSize-2 or stackSize-3.
+ *
+ * @param i stack index of the first of the two runs to merge
+ */
+ private void mergeAt(int i) {
+ assert stackSize >= 2;
+ assert i >= 0;
+ assert i == stackSize - 2 || i == stackSize - 3;
+
+ int base1 = runBase[i];
+ int len1 = runLen[i];
+ int base2 = runBase[i + 1];
+ int len2 = runLen[i + 1];
+ assert len1 > 0 && len2 > 0;
+ assert base1 + len1 == base2;
+
+ /*
+ * Record the length of the combined runs; if i is the 3rd-last
+ * run now, also slide over the last run (which isn't involved
+ * in this merge). The current run (i+1) goes away in any case.
+ */
+ runLen[i] = len1 + len2;
+ if (i == stackSize - 3) {
+ runBase[i + 1] = runBase[i + 2];
+ runLen[i + 1] = runLen[i + 2];
+ }
+ stackSize--;
+
+ /*
+ * Find where the first element of run2 goes in run1. Prior elements
+ * in run1 can be ignored (because they're already in place).
+ */
+ int k = gallopRight(a[base2], a, base1, len1, 0, c);
+ assert k >= 0;
+ base1 += k;
+ len1 -= k;
+ if (len1 == 0)
+ return;
+
+ /*
+ * Find where the last element of run1 goes in run2. Subsequent elements
+ * in run2 can be ignored (because they're already in place).
+ */
+ len2 = gallopLeft(a[base1 + len1 - 1], a, base2, len2, len2 - 1, c);
+ assert len2 >= 0;
+ if (len2 == 0)
+ return;
+
+ // Merge remaining runs, using tmp array with min(len1, len2) elements
+ if (len1 <= len2)
+ mergeLo(base1, len1, base2, len2);
+ else
+ mergeHi(base1, len1, base2, len2);
+ }
+
+ /**
+ * Locates the position at which to insert the specified key into the
+ * specified sorted range; if the range contains an element equal to key,
+ * returns the index of the leftmost equal element.
+ *
+ * @param key the key whose insertion point to search for
+ * @param a the array in which to search
+ * @param base the index of the first element in the range
+ * @param len the length of the range; must be > 0
+ * @param hint the index at which to begin the search, 0 <= hint < n.
+ * The closer hint is to the result, the faster this method will run.
+ * @param c the comparator used to order the range, and to search
+ * @return the int k, 0 <= k <= n such that a[b + k - 1] < key <= a[b + k],
+ * pretending that a[b - 1] is minus infinity and a[b + n] is infinity.
+ * In other words, key belongs at index b + k; or in other words,
+ * the first k elements of a should precede key, and the last n - k
+ * should follow it.
+ */
+ private static int gallopLeft(T key, T[] a, int base, int len, int hint,
+ Comparator super T> c) {
+ assert len > 0 && hint >= 0 && hint < len;
+ int lastOfs = 0;
+ int ofs = 1;
+ if (c.compare(key, a[base + hint]) > 0) {
+ // Gallop right until a[base+hint+lastOfs] < key <= a[base+hint+ofs]
+ int maxOfs = len - hint;
+ while (ofs < maxOfs && c.compare(key, a[base + hint + ofs]) > 0) {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if (ofs <= 0) // int overflow
+ ofs = maxOfs;
+ }
+ if (ofs > maxOfs)
+ ofs = maxOfs;
+
+ // Make offsets relative to base
+ lastOfs += hint;
+ ofs += hint;
+ } else { // key <= a[base + hint]
+ // Gallop left until a[base+hint-ofs] < key <= a[base+hint-lastOfs]
+ final int maxOfs = hint + 1;
+ while (ofs < maxOfs && c.compare(key, a[base + hint - ofs]) <= 0) {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if (ofs <= 0) // int overflow
+ ofs = maxOfs;
+ }
+ if (ofs > maxOfs)
+ ofs = maxOfs;
+
+ // Make offsets relative to base
+ int tmp = lastOfs;
+ lastOfs = hint - ofs;
+ ofs = hint - tmp;
+ }
+ assert -1 <= lastOfs && lastOfs < ofs && ofs <= len;
+
+ /*
+ * Now a[base+lastOfs] < key <= a[base+ofs], so key belongs somewhere
+ * to the right of lastOfs but no farther right than ofs. Do a binary
+ * search, with invariant a[base + lastOfs - 1] < key <= a[base + ofs].
+ */
+ lastOfs++;
+ while (lastOfs < ofs) {
+ int m = lastOfs + ((ofs - lastOfs) >>> 1);
+
+ if (c.compare(key, a[base + m]) > 0)
+ lastOfs = m + 1; // a[base + m] < key
+ else
+ ofs = m; // key <= a[base + m]
+ }
+ assert lastOfs == ofs; // so a[base + ofs - 1] < key <= a[base + ofs]
+ return ofs;
+ }
+
+ /**
+ * Like gallopLeft, except that if the range contains an element equal to
+ * key, gallopRight returns the index after the rightmost equal element.
+ *
+ * @param key the key whose insertion point to search for
+ * @param a the array in which to search
+ * @param base the index of the first element in the range
+ * @param len the length of the range; must be > 0
+ * @param hint the index at which to begin the search, 0 <= hint < n.
+ * The closer hint is to the result, the faster this method will run.
+ * @param c the comparator used to order the range, and to search
+ * @return the int k, 0 <= k <= n such that a[b + k - 1] <= key < a[b + k]
+ */
+ private static int gallopRight(T key, T[] a, int base, int len,
+ int hint, Comparator super T> c) {
+ assert len > 0 && hint >= 0 && hint < len;
+
+ int ofs = 1;
+ int lastOfs = 0;
+ if (c.compare(key, a[base + hint]) < 0) {
+ // Gallop left until a[b+hint - ofs] <= key < a[b+hint - lastOfs]
+ int maxOfs = hint + 1;
+ while (ofs < maxOfs && c.compare(key, a[base + hint - ofs]) < 0) {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if (ofs <= 0) // int overflow
+ ofs = maxOfs;
+ }
+ if (ofs > maxOfs)
+ ofs = maxOfs;
+
+ // Make offsets relative to b
+ int tmp = lastOfs;
+ lastOfs = hint - ofs;
+ ofs = hint - tmp;
+ } else { // a[b + hint] <= key
+ // Gallop right until a[b+hint + lastOfs] <= key < a[b+hint + ofs]
+ int maxOfs = len - hint;
+ while (ofs < maxOfs && c.compare(key, a[base + hint + ofs]) >= 0) {
+ lastOfs = ofs;
+ ofs = (ofs << 1) + 1;
+ if (ofs <= 0) // int overflow
+ ofs = maxOfs;
+ }
+ if (ofs > maxOfs)
+ ofs = maxOfs;
+
+ // Make offsets relative to b
+ lastOfs += hint;
+ ofs += hint;
+ }
+ assert -1 <= lastOfs && lastOfs < ofs && ofs <= len;
+
+ /*
+ * Now a[b + lastOfs] <= key < a[b + ofs], so key belongs somewhere to
+ * the right of lastOfs but no farther right than ofs. Do a binary
+ * search, with invariant a[b + lastOfs - 1] <= key < a[b + ofs].
+ */
+ lastOfs++;
+ while (lastOfs < ofs) {
+ int m = lastOfs + ((ofs - lastOfs) >>> 1);
+
+ if (c.compare(key, a[base + m]) < 0)
+ ofs = m; // key < a[b + m]
+ else
+ lastOfs = m + 1; // a[b + m] <= key
+ }
+ assert lastOfs == ofs; // so a[b + ofs - 1] <= key < a[b + ofs]
+ return ofs;
+ }
+
+ /**
+ * Merges two adjacent runs in place, in a stable fashion. The first
+ * element of the first run must be greater than the first element of the
+ * second run (a[base1] > a[base2]), and the last element of the first run
+ * (a[base1 + len1-1]) must be greater than all elements of the second run.
+ *
+ * For performance, this method should be called only when len1 <= len2;
+ * its twin, mergeHi should be called if len1 >= len2. (Either method
+ * may be called if len1 == len2.)
+ *
+ * @param base1 index of first element in first run to be merged
+ * @param len1 length of first run to be merged (must be > 0)
+ * @param base2 index of first element in second run to be merged
+ * (must be aBase + aLen)
+ * @param len2 length of second run to be merged (must be > 0)
+ */
+ private void mergeLo(int base1, int len1, int base2, int len2) {
+ assert len1 > 0 && len2 > 0 && base1 + len1 == base2;
+
+ // Copy first run into temp array
+ T[] a = this.a; // For performance
+ T[] tmp = ensureCapacity(len1);
+ System.arraycopy(a, base1, tmp, 0, len1);
+
+ int cursor1 = 0; // Indexes into tmp array
+ int cursor2 = base2; // Indexes int a
+ int dest = base1; // Indexes int a
+
+ // Move first element of second run and deal with degenerate cases
+ a[dest++] = a[cursor2++];
+ if (--len2 == 0) {
+ System.arraycopy(tmp, cursor1, a, dest, len1);
+ return;
+ }
+ if (len1 == 1) {
+ System.arraycopy(a, cursor2, a, dest, len2);
+ a[dest + len2] = tmp[cursor1]; // Last elt of run 1 to end of merge
+ return;
+ }
+
+ Comparator super T> c = this.c; // Use local variable for performance
+ int minGallop = this.minGallop; // " " " " "
+ outer:
+ while (true) {
+ int count1 = 0; // Number of times in a row that first run won
+ int count2 = 0; // Number of times in a row that second run won
+
+ /*
+ * Do the straightforward thing until (if ever) one run starts
+ * winning consistently.
+ */
+ do {
+ assert len1 > 1 && len2 > 0;
+ if (c.compare(a[cursor2], tmp[cursor1]) < 0) {
+ a[dest++] = a[cursor2++];
+ count2++;
+ count1 = 0;
+ if (--len2 == 0)
+ break outer;
+ } else {
+ a[dest++] = tmp[cursor1++];
+ count1++;
+ count2 = 0;
+ if (--len1 == 1)
+ break outer;
+ }
+ } while ((count1 | count2) < minGallop);
+
+ /*
+ * One run is winning so consistently that galloping may be a
+ * huge win. So try that, and continue galloping until (if ever)
+ * neither run appears to be winning consistently anymore.
+ */
+ do {
+ assert len1 > 1 && len2 > 0;
+ count1 = gallopRight(a[cursor2], tmp, cursor1, len1, 0, c);
+ if (count1 != 0) {
+ System.arraycopy(tmp, cursor1, a, dest, count1);
+ dest += count1;
+ cursor1 += count1;
+ len1 -= count1;
+ if (len1 <= 1) // len1 == 1 || len1 == 0
+ break outer;
+ }
+ a[dest++] = a[cursor2++];
+ if (--len2 == 0)
+ break outer;
+
+ count2 = gallopLeft(tmp[cursor1], a, cursor2, len2, 0, c);
+ if (count2 != 0) {
+ System.arraycopy(a, cursor2, a, dest, count2);
+ dest += count2;
+ cursor2 += count2;
+ len2 -= count2;
+ if (len2 == 0)
+ break outer;
+ }
+ a[dest++] = tmp[cursor1++];
+ if (--len1 == 1)
+ break outer;
+ minGallop--;
+ } while (count1 >= MIN_GALLOP | count2 >= MIN_GALLOP);
+ if (minGallop < 0)
+ minGallop = 0;
+ minGallop += 2; // Penalize for leaving gallop mode
+ } // End of "outer" loop
+ this.minGallop = minGallop < 1 ? 1 : minGallop; // Write back to field
+
+ if (len1 == 1) {
+ assert len2 > 0;
+ System.arraycopy(a, cursor2, a, dest, len2);
+ a[dest + len2] = tmp[cursor1]; // Last elt of run 1 to end of merge
+ } else if (len1 == 0) {
+ throw new IllegalArgumentException(
+ "Comparison method violates its general contract!");
+ } else {
+ assert len2 == 0;
+ assert len1 > 1;
+ System.arraycopy(tmp, cursor1, a, dest, len1);
+ }
+ }
+
+ /**
+ * Like mergeLo, except that this method should be called only if
+ * len1 >= len2; mergeLo should be called if len1 <= len2. (Either method
+ * may be called if len1 == len2.)
+ *
+ * @param base1 index of first element in first run to be merged
+ * @param len1 length of first run to be merged (must be > 0)
+ * @param base2 index of first element in second run to be merged
+ * (must be aBase + aLen)
+ * @param len2 length of second run to be merged (must be > 0)
+ */
+ private void mergeHi(int base1, int len1, int base2, int len2) {
+ assert len1 > 0 && len2 > 0 && base1 + len1 == base2;
+
+ // Copy second run into temp array
+ T[] a = this.a; // For performance
+ T[] tmp = ensureCapacity(len2);
+ System.arraycopy(a, base2, tmp, 0, len2);
+
+ int cursor1 = base1 + len1 - 1; // Indexes into a
+ int cursor2 = len2 - 1; // Indexes into tmp array
+ int dest = base2 + len2 - 1; // Indexes into a
+
+ // Move last element of first run and deal with degenerate cases
+ a[dest--] = a[cursor1--];
+ if (--len1 == 0) {
+ System.arraycopy(tmp, 0, a, dest - (len2 - 1), len2);
+ return;
+ }
+ if (len2 == 1) {
+ dest -= len1;
+ cursor1 -= len1;
+ System.arraycopy(a, cursor1 + 1, a, dest + 1, len1);
+ a[dest] = tmp[cursor2];
+ return;
+ }
+
+ Comparator super T> c = this.c; // Use local variable for performance
+ int minGallop = this.minGallop; // " " " " "
+ outer:
+ while (true) {
+ int count1 = 0; // Number of times in a row that first run won
+ int count2 = 0; // Number of times in a row that second run won
+
+ /*
+ * Do the straightforward thing until (if ever) one run
+ * appears to win consistently.
+ */
+ do {
+ assert len1 > 0 && len2 > 1;
+ if (c.compare(tmp[cursor2], a[cursor1]) < 0) {
+ a[dest--] = a[cursor1--];
+ count1++;
+ count2 = 0;
+ if (--len1 == 0)
+ break outer;
+ } else {
+ a[dest--] = tmp[cursor2--];
+ count2++;
+ count1 = 0;
+ if (--len2 == 1)
+ break outer;
+ }
+ } while ((count1 | count2) < minGallop);
+
+ /*
+ * One run is winning so consistently that galloping may be a
+ * huge win. So try that, and continue galloping until (if ever)
+ * neither run appears to be winning consistently anymore.
+ */
+ do {
+ assert len1 > 0 && len2 > 1;
+ count1 = len1 - gallopRight(tmp[cursor2], a, base1, len1, len1 - 1, c);
+ if (count1 != 0) {
+ dest -= count1;
+ cursor1 -= count1;
+ len1 -= count1;
+ System.arraycopy(a, cursor1 + 1, a, dest + 1, count1);
+ if (len1 == 0)
+ break outer;
+ }
+ a[dest--] = tmp[cursor2--];
+ if (--len2 == 1)
+ break outer;
+
+ count2 = len2 - gallopLeft(a[cursor1], tmp, 0, len2, len2 - 1, c);
+ if (count2 != 0) {
+ dest -= count2;
+ cursor2 -= count2;
+ len2 -= count2;
+ System.arraycopy(tmp, cursor2 + 1, a, dest + 1, count2);
+ if (len2 <= 1) // len2 == 1 || len2 == 0
+ break outer;
+ }
+ a[dest--] = a[cursor1--];
+ if (--len1 == 0)
+ break outer;
+ minGallop--;
+ } while (count1 >= MIN_GALLOP | count2 >= MIN_GALLOP);
+ if (minGallop < 0)
+ minGallop = 0;
+ minGallop += 2; // Penalize for leaving gallop mode
+ } // End of "outer" loop
+ this.minGallop = minGallop < 1 ? 1 : minGallop; // Write back to field
+
+ if (len2 == 1) {
+ assert len1 > 0;
+ dest -= len1;
+ cursor1 -= len1;
+ System.arraycopy(a, cursor1 + 1, a, dest + 1, len1);
+ a[dest] = tmp[cursor2]; // Move first elt of run2 to front of merge
+ } else if (len2 == 0) {
+ throw new IllegalArgumentException(
+ "Comparison method violates its general contract!");
+ } else {
+ assert len1 == 0;
+ assert len2 > 0;
+ System.arraycopy(tmp, 0, a, dest - (len2 - 1), len2);
+ }
+ }
+
+ /**
+ * Ensures that the external array tmp has at least the specified
+ * number of elements, increasing its size if necessary. The size
+ * increases exponentially to ensure amortized linear time complexity.
+ *
+ * @param minCapacity the minimum required capacity of the tmp array
+ * @return tmp, whether or not it grew
+ */
+ private T[] ensureCapacity(int minCapacity) {
+ if (tmp.length < minCapacity) {
+ // Compute smallest power of 2 > minCapacity
+ int newSize = minCapacity;
+ newSize |= newSize >> 1;
+ newSize |= newSize >> 2;
+ newSize |= newSize >> 4;
+ newSize |= newSize >> 8;
+ newSize |= newSize >> 16;
+ newSize++;
+
+ if (newSize < 0) // Not bloody likely!
+ newSize = minCapacity;
+ else
+ newSize = Math.min(newSize, a.length >>> 1);
+
+ @SuppressWarnings({"unchecked", "UnnecessaryLocalVariable"})
+ T[] newArray = (T[]) new Object[newSize];
+ tmp = newArray;
+ }
+ return tmp;
+ }
+
+ /**
+ * Checks that fromIndex and toIndex are in range, and throws an
+ * appropriate exception if they aren't.
+ *
+ * @param arrayLen the length of the array
+ * @param fromIndex the index of the first element of the range
+ * @param toIndex the index after the last element of the range
+ * @throws IllegalArgumentException if fromIndex > toIndex
+ * @throws ArrayIndexOutOfBoundsException if fromIndex < 0
+ * or toIndex > arrayLen
+ */
+ private static void rangeCheck(int arrayLen, int fromIndex, int toIndex) {
+ if (fromIndex > toIndex)
+ throw new IllegalArgumentException("fromIndex(" + fromIndex +
+ ") > toIndex(" + toIndex+")");
+ if (fromIndex < 0)
+ throw new ArrayIndexOutOfBoundsException(fromIndex);
+ if (toIndex > arrayLen)
+ throw new ArrayIndexOutOfBoundsException(toIndex);
+ }
+}
diff --git a/src/share/classes/java/util/concurrent/ConcurrentLinkedQueue.java b/src/share/classes/java/util/concurrent/ConcurrentLinkedQueue.java
index fafbcc01704c682b8abd5c2bd7e993c77a0eb95b..5e31adea247d3685b0ff46f13e85c7ee7c78990b 100644
--- a/src/share/classes/java/util/concurrent/ConcurrentLinkedQueue.java
+++ b/src/share/classes/java/util/concurrent/ConcurrentLinkedQueue.java
@@ -34,9 +34,13 @@
*/
package java.util.concurrent;
-import java.util.*;
-import java.util.concurrent.atomic.*;
+import java.util.AbstractQueue;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+import java.util.Queue;
/**
* An unbounded thread-safe {@linkplain Queue queue} based on linked nodes.
@@ -47,9 +51,9 @@ import java.util.concurrent.atomic.*;
* queue the shortest time. New elements
* are inserted at the tail of the queue, and the queue retrieval
* operations obtain elements at the head of the queue.
- * A ConcurrentLinkedQueue is an appropriate choice when
+ * A {@code ConcurrentLinkedQueue} is an appropriate choice when
* many threads will share access to a common collection.
- * This queue does not permit null elements.
+ * This queue does not permit {@code null} elements.
*
* This implementation employs an efficient "wait-free"
* algorithm based on one described in by Maged M. Michael and Michael L. Scott.
*
- * Beware that, unlike in most collections, the size method
+ *
Beware that, unlike in most collections, the {@code size} method
* is NOT a constant-time operation. Because of the
* asynchronous nature of these queues, determining the current number
* of elements requires a traversal of the elements.
@@ -87,104 +91,158 @@ public class ConcurrentLinkedQueue extends AbstractQueue
private static final long serialVersionUID = 196745693267521676L;
/*
- * This is a straight adaptation of Michael & Scott algorithm.
- * For explanation, read the paper. The only (minor) algorithmic
- * difference is that this version supports lazy deletion of
- * internal nodes (method remove(Object)) -- remove CAS'es item
- * fields to null. The normal queue operations unlink but then
- * pass over nodes with null item fields. Similarly, iteration
- * methods ignore those with nulls.
+ * This is a modification of the Michael & Scott algorithm,
+ * adapted for a garbage-collected environment, with support for
+ * interior node deletion (to support remove(Object)). For
+ * explanation, read the paper.
*
- * Also note that like most non-blocking algorithms in this
- * package, this implementation relies on the fact that in garbage
+ * Note that like most non-blocking algorithms in this package,
+ * this implementation relies on the fact that in garbage
* collected systems, there is no possibility of ABA problems due
* to recycled nodes, so there is no need to use "counted
* pointers" or related techniques seen in versions used in
* non-GC'ed settings.
+ *
+ * The fundamental invariants are:
+ * - There is exactly one (last) Node with a null next reference,
+ * which is CASed when enqueueing. This last Node can be
+ * reached in O(1) time from tail, but tail is merely an
+ * optimization - it can always be reached in O(N) time from
+ * head as well.
+ * - The elements contained in the queue are the non-null items in
+ * Nodes that are reachable from head. CASing the item
+ * reference of a Node to null atomically removes it from the
+ * queue. Reachability of all elements from head must remain
+ * true even in the case of concurrent modifications that cause
+ * head to advance. A dequeued Node may remain in use
+ * indefinitely due to creation of an Iterator or simply a
+ * poll() that has lost its time slice.
+ *
+ * The above might appear to imply that all Nodes are GC-reachable
+ * from a predecessor dequeued Node. That would cause two problems:
+ * - allow a rogue Iterator to cause unbounded memory retention
+ * - cause cross-generational linking of old Nodes to new Nodes if
+ * a Node was tenured while live, which generational GCs have a
+ * hard time dealing with, causing repeated major collections.
+ * However, only non-deleted Nodes need to be reachable from
+ * dequeued Nodes, and reachability does not necessarily have to
+ * be of the kind understood by the GC. We use the trick of
+ * linking a Node that has just been dequeued to itself. Such a
+ * self-link implicitly means to advance to head.
+ *
+ * Both head and tail are permitted to lag. In fact, failing to
+ * update them every time one could is a significant optimization
+ * (fewer CASes). This is controlled by local "hops" variables
+ * that only trigger helping-CASes after experiencing multiple
+ * lags.
+ *
+ * Since head and tail are updated concurrently and independently,
+ * it is possible for tail to lag behind head (why not)?
+ *
+ * CASing a Node's item reference to null atomically removes the
+ * element from the queue. Iterators skip over Nodes with null
+ * items. Prior implementations of this class had a race between
+ * poll() and remove(Object) where the same element would appear
+ * to be successfully removed by two concurrent operations. The
+ * method remove(Object) also lazily unlinks deleted Nodes, but
+ * this is merely an optimization.
+ *
+ * When constructing a Node (before enqueuing it) we avoid paying
+ * for a volatile write to item by using lazySet instead of a
+ * normal write. This allows the cost of enqueue to be
+ * "one-and-a-half" CASes.
+ *
+ * Both head and tail may or may not point to a Node with a
+ * non-null item. If the queue is empty, all items must of course
+ * be null. Upon creation, both head and tail refer to a dummy
+ * Node with null item. Both head and tail are only updated using
+ * CAS, so they never regress, although again this is merely an
+ * optimization.
*/
private static class Node {
private volatile E item;
private volatile Node next;
- private static final
- AtomicReferenceFieldUpdater
- nextUpdater =
- AtomicReferenceFieldUpdater.newUpdater
- (Node.class, Node.class, "next");
- private static final
- AtomicReferenceFieldUpdater
- itemUpdater =
- AtomicReferenceFieldUpdater.newUpdater
- (Node.class, Object.class, "item");
-
- Node(E x) { item = x; }
-
- Node(E x, Node n) { item = x; next = n; }
+ Node(E item) {
+ // Piggyback on imminent casNext()
+ lazySetItem(item);
+ }
E getItem() {
return item;
}
boolean casItem(E cmp, E val) {
- return itemUpdater.compareAndSet(this, cmp, val);
+ return UNSAFE.compareAndSwapObject(this, itemOffset, cmp, val);
}
void setItem(E val) {
- itemUpdater.set(this, val);
+ item = val;
}
- Node getNext() {
- return next;
+ void lazySetItem(E val) {
+ UNSAFE.putOrderedObject(this, itemOffset, val);
}
- boolean casNext(Node cmp, Node val) {
- return nextUpdater.compareAndSet(this, cmp, val);
+ void lazySetNext(Node val) {
+ UNSAFE.putOrderedObject(this, nextOffset, val);
}
- void setNext(Node val) {
- nextUpdater.set(this, val);
+ Node getNext() {
+ return next;
}
- }
+ boolean casNext(Node cmp, Node val) {
+ return UNSAFE.compareAndSwapObject(this, nextOffset, cmp, val);
+ }
- private static final
- AtomicReferenceFieldUpdater
- tailUpdater =
- AtomicReferenceFieldUpdater.newUpdater
- (ConcurrentLinkedQueue.class, Node.class, "tail");
- private static final
- AtomicReferenceFieldUpdater
- headUpdater =
- AtomicReferenceFieldUpdater.newUpdater
- (ConcurrentLinkedQueue.class, Node.class, "head");
+ // Unsafe mechanics
- private boolean casTail(Node cmp, Node val) {
- return tailUpdater.compareAndSet(this, cmp, val);
+ private static final sun.misc.Unsafe UNSAFE =
+ sun.misc.Unsafe.getUnsafe();
+ private static final long nextOffset =
+ objectFieldOffset(UNSAFE, "next", Node.class);
+ private static final long itemOffset =
+ objectFieldOffset(UNSAFE, "item", Node.class);
}
- private boolean casHead(Node cmp, Node val) {
- return headUpdater.compareAndSet(this, cmp, val);
- }
-
-
/**
- * Pointer to header node, initialized to a dummy node. The first
- * actual node is at head.getNext().
+ * A node from which the first live (non-deleted) node (if any)
+ * can be reached in O(1) time.
+ * Invariants:
+ * - all live nodes are reachable from head via succ()
+ * - head != null
+ * - (tmp = head).next != tmp || tmp != head
+ * Non-invariants:
+ * - head.item may or may not be null.
+ * - it is permitted for tail to lag behind head, that is, for tail
+ * to not be reachable from head!
*/
- private transient volatile Node head = new Node(null, null);
+ private transient volatile Node head = new Node(null);
- /** Pointer to last node on list **/
+ /**
+ * A node from which the last node on list (that is, the unique
+ * node with node.next == null) can be reached in O(1) time.
+ * Invariants:
+ * - the last node is always reachable from tail via succ()
+ * - tail != null
+ * Non-invariants:
+ * - tail.item may or may not be null.
+ * - it is permitted for tail to lag behind head, that is, for tail
+ * to not be reachable from head!
+ * - tail.next may or may not be self-pointing to tail.
+ */
private transient volatile Node tail = head;
/**
- * Creates a ConcurrentLinkedQueue that is initially empty.
+ * Creates a {@code ConcurrentLinkedQueue} that is initially empty.
*/
public ConcurrentLinkedQueue() {}
/**
- * Creates a ConcurrentLinkedQueue
+ * Creates a {@code ConcurrentLinkedQueue}
* initially containing the elements of the given collection,
* added in traversal order of the collection's iterator.
* @param c the collection of elements to initially contain
@@ -201,115 +259,143 @@ public class ConcurrentLinkedQueue extends AbstractQueue
/**
* Inserts the specified element at the tail of this queue.
*
- * @return true (as specified by {@link Collection#add})
+ * @return {@code true} (as specified by {@link Collection#add})
* @throws NullPointerException if the specified element is null
*/
public boolean add(E e) {
return offer(e);
}
+ /**
+ * We don't bother to update head or tail pointers if fewer than
+ * HOPS links from "true" location. We assume that volatile
+ * writes are significantly more expensive than volatile reads.
+ */
+ private static final int HOPS = 1;
+
+ /**
+ * Try to CAS head to p. If successful, repoint old head to itself
+ * as sentinel for succ(), below.
+ */
+ final void updateHead(Node h, Node p) {
+ if (h != p && casHead(h, p))
+ h.lazySetNext(h);
+ }
+
+ /**
+ * Returns the successor of p, or the head node if p.next has been
+ * linked to self, which will only be true if traversing with a
+ * stale pointer that is now off the list.
+ */
+ final Node succ(Node p) {
+ Node next = p.getNext();
+ return (p == next) ? head : next;
+ }
+
/**
* Inserts the specified element at the tail of this queue.
*
- * @return true (as specified by {@link Queue#offer})
+ * @return {@code true} (as specified by {@link Queue#offer})
* @throws NullPointerException if the specified element is null
*/
public boolean offer(E e) {
if (e == null) throw new NullPointerException();
- Node n = new Node(e, null);
+ Node n = new Node(e);
+ retry:
for (;;) {
Node t = tail;
- Node s = t.getNext();
- if (t == tail) {
- if (s == null) {
- if (t.casNext(s, n)) {
- casTail(t, n);
- return true;
- }
+ Node p = t;
+ for (int hops = 0; ; hops++) {
+ Node next = succ(p);
+ if (next != null) {
+ if (hops > HOPS && t != tail)
+ continue retry;
+ p = next;
+ } else if (p.casNext(null, n)) {
+ if (hops >= HOPS)
+ casTail(t, n); // Failure is OK.
+ return true;
} else {
- casTail(t, s);
+ p = succ(p);
}
}
}
}
public E poll() {
- for (;;) {
- Node h = head;
- Node t = tail;
- Node first = h.getNext();
- if (h == head) {
- if (h == t) {
- if (first == null)
- return null;
- else
- casTail(t, first);
- } else if (casHead(h, first)) {
- E item = first.getItem();
- if (item != null) {
- first.setItem(null);
- return item;
- }
- // else skip over deleted item, continue loop,
+ Node h = head;
+ Node p = h;
+ for (int hops = 0; ; hops++) {
+ E item = p.getItem();
+
+ if (item != null && p.casItem(item, null)) {
+ if (hops >= HOPS) {
+ Node q = p.getNext();
+ updateHead(h, (q != null) ? q : p);
}
+ return item;
+ }
+ Node next = succ(p);
+ if (next == null) {
+ updateHead(h, p);
+ break;
}
+ p = next;
}
+ return null;
}
- public E peek() { // same as poll except don't remove item
+ public E peek() {
+ Node h = head;
+ Node p = h;
+ E item;
for (;;) {
- Node h = head;
- Node t = tail;
- Node first = h.getNext();
- if (h == head) {
- if (h == t) {
- if (first == null)
- return null;
- else
- casTail(t, first);
- } else {
- E item = first.getItem();
- if (item != null)
- return item;
- else // remove deleted node and continue
- casHead(h, first);
- }
+ item = p.getItem();
+ if (item != null)
+ break;
+ Node next = succ(p);
+ if (next == null) {
+ break;
}
+ p = next;
}
+ updateHead(h, p);
+ return item;
}
/**
- * Returns the first actual (non-header) node on list. This is yet
- * another variant of poll/peek; here returning out the first
- * node, not element (so we cannot collapse with peek() without
- * introducing race.)
+ * Returns the first live (non-deleted) node on list, or null if none.
+ * This is yet another variant of poll/peek; here returning the
+ * first node, not element. We could make peek() a wrapper around
+ * first(), but that would cost an extra volatile read of item,
+ * and the need to add a retry loop to deal with the possibility
+ * of losing a race to a concurrent poll().
*/
Node first() {
+ Node h = head;
+ Node p = h;
+ Node result;
for (;;) {
- Node h = head;
- Node t = tail;
- Node first = h.getNext();
- if (h == head) {
- if (h == t) {
- if (first == null)
- return null;
- else
- casTail(t, first);
- } else {
- if (first.getItem() != null)
- return first;
- else // remove deleted node and continue
- casHead(h, first);
- }
+ E item = p.getItem();
+ if (item != null) {
+ result = p;
+ break;
+ }
+ Node next = succ(p);
+ if (next == null) {
+ result = null;
+ break;
}
+ p = next;
}
+ updateHead(h, p);
+ return result;
}
-
/**
- * Returns true if this queue contains no elements.
+ * Returns {@code true} if this queue contains no elements.
*
- * @return true if this queue contains no elements
+ * @return {@code true} if this queue contains no elements
*/
public boolean isEmpty() {
return first() == null;
@@ -317,8 +403,8 @@ public class ConcurrentLinkedQueue extends AbstractQueue
/**
* Returns the number of elements in this queue. If this queue
- * contains more than Integer.MAX_VALUE elements, returns
- * Integer.MAX_VALUE .
+ * contains more than {@code Integer.MAX_VALUE} elements, returns
+ * {@code Integer.MAX_VALUE}.
*
* Beware that, unlike in most collections, this method is
* NOT a constant-time operation. Because of the
@@ -329,7 +415,7 @@ public class ConcurrentLinkedQueue extends AbstractQueue
*/
public int size() {
int count = 0;
- for (Node p = first(); p != null; p = p.getNext()) {
+ for (Node p = first(); p != null; p = succ(p)) {
if (p.getItem() != null) {
// Collections.size() spec says to max out
if (++count == Integer.MAX_VALUE)
@@ -340,16 +426,16 @@ public class ConcurrentLinkedQueue extends AbstractQueue
}
/**
- * Returns true if this queue contains the specified element.
- * More formally, returns true if and only if this queue contains
- * at least one element e such that o.equals(e) .
+ * Returns {@code true} if this queue contains the specified element.
+ * More formally, returns {@code true} if and only if this queue contains
+ * at least one element {@code e} such that {@code o.equals(e)}.
*
* @param o object to be checked for containment in this queue
- * @return true if this queue contains the specified element
+ * @return {@code true} if this queue contains the specified element
*/
public boolean contains(Object o) {
if (o == null) return false;
- for (Node p = first(); p != null; p = p.getNext()) {
+ for (Node p = first(); p != null; p = succ(p)) {
E item = p.getItem();
if (item != null &&
o.equals(item))
@@ -360,23 +446,29 @@ public class ConcurrentLinkedQueue extends AbstractQueue
/**
* Removes a single instance of the specified element from this queue,
- * if it is present. More formally, removes an element e such
- * that o.equals(e) , if this queue contains one or more such
+ * if it is present. More formally, removes an element {@code e} such
+ * that {@code o.equals(e)}, if this queue contains one or more such
* elements.
- * Returns true if this queue contained the specified element
+ * Returns {@code true} if this queue contained the specified element
* (or equivalently, if this queue changed as a result of the call).
*
* @param o element to be removed from this queue, if present
- * @return true if this queue changed as a result of the call
+ * @return {@code true} if this queue changed as a result of the call
*/
public boolean remove(Object o) {
if (o == null) return false;
- for (Node p = first(); p != null; p = p.getNext()) {
+ Node pred = null;
+ for (Node p = first(); p != null; p = succ(p)) {
E item = p.getItem();
if (item != null &&
o.equals(item) &&
- p.casItem(item, null))
+ p.casItem(item, null)) {
+ Node next = succ(p);
+ if (pred != null && next != null)
+ pred.casNext(p, next);
return true;
+ }
+ pred = p;
}
return false;
}
@@ -397,7 +489,7 @@ public class ConcurrentLinkedQueue extends AbstractQueue
public Object[] toArray() {
// Use ArrayList to deal with resizing.
ArrayList al = new ArrayList();
- for (Node p = first(); p != null; p = p.getNext()) {
+ for (Node p = first(); p != null; p = succ(p)) {
E item = p.getItem();
if (item != null)
al.add(item);
@@ -415,22 +507,22 @@ public class ConcurrentLinkedQueue extends AbstractQueue
* If this queue fits in the specified array with room to spare
* (i.e., the array has more elements than this queue), the element in
* the array immediately following the end of the queue is set to
- * null .
+ * {@code null}.
*
*
Like the {@link #toArray()} method, this method acts as bridge between
* array-based and collection-based APIs. Further, this method allows
* precise control over the runtime type of the output array, and may,
* under certain circumstances, be used to save allocation costs.
*
- *
Suppose x is a queue known to contain only strings.
+ *
Suppose {@code x} is a queue known to contain only strings.
* The following code can be used to dump the queue into a newly
- * allocated array of String :
+ * allocated array of {@code String}:
*
*
* String[] y = x.toArray(new String[0]);
*
- * Note that toArray(new Object[0]) is identical in function to
- * toArray() .
+ * Note that {@code toArray(new Object[0])} is identical in function to
+ * {@code toArray()}.
*
* @param a the array into which the elements of the queue are to
* be stored, if it is big enough; otherwise, a new array of the
@@ -441,11 +533,12 @@ public class ConcurrentLinkedQueue extends AbstractQueue
* this queue
* @throws NullPointerException if the specified array is null
*/
+ @SuppressWarnings("unchecked")
public T[] toArray(T[] a) {
// try to use sent-in array
int k = 0;
Node p;
- for (p = first(); p != null && k < a.length; p = p.getNext()) {
+ for (p = first(); p != null && k < a.length; p = succ(p)) {
E item = p.getItem();
if (item != null)
a[k++] = (T)item;
@@ -458,7 +551,7 @@ public class ConcurrentLinkedQueue extends AbstractQueue
// If won't fit, use ArrayList version
ArrayList al = new ArrayList();
- for (Node q = first(); q != null; q = q.getNext()) {
+ for (Node q = first(); q != null; q = succ(q)) {
E item = q.getItem();
if (item != null)
al.add(item);
@@ -469,7 +562,8 @@ public class ConcurrentLinkedQueue extends AbstractQueue
/**
* Returns an iterator over the elements in this queue in proper sequence.
* The returned iterator is a "weakly consistent" iterator that
- * will never throw {@link ConcurrentModificationException},
+ * will never throw {@link java.util.ConcurrentModificationException
+ * ConcurrentModificationException},
* and guarantees to traverse elements as they existed upon
* construction of the iterator, and may (but is not guaranteed to)
* reflect any modifications subsequent to construction.
@@ -511,7 +605,15 @@ public class ConcurrentLinkedQueue extends AbstractQueue
lastRet = nextNode;
E x = nextItem;
- Node p = (nextNode == null)? first() : nextNode.getNext();
+ Node pred, p;
+ if (nextNode == null) {
+ p = first();
+ pred = null;
+ } else {
+ pred = nextNode;
+ p = succ(nextNode);
+ }
+
for (;;) {
if (p == null) {
nextNode = null;
@@ -523,8 +625,13 @@ public class ConcurrentLinkedQueue extends AbstractQueue
nextNode = p;
nextItem = item;
return x;
- } else // skip over nulls
- p = p.getNext();
+ } else {
+ // skip over nulls
+ Node next = succ(p);
+ if (pred != null && next != null)
+ pred.casNext(p, next);
+ p = next;
+ }
}
}
@@ -549,7 +656,7 @@ public class ConcurrentLinkedQueue extends AbstractQueue
/**
* Save the state to a stream (that is, serialize it).
*
- * @serialData All of the elements (each an E ) in
+ * @serialData All of the elements (each an {@code E}) in
* the proper order, followed by a null
* @param s the stream
*/
@@ -560,7 +667,7 @@ public class ConcurrentLinkedQueue extends AbstractQueue
s.defaultWriteObject();
// Write out all elements in the proper order.
- for (Node p = first(); p != null; p = p.getNext()) {
+ for (Node p = first(); p != null; p = succ(p)) {
Object item = p.getItem();
if (item != null)
s.writeObject(item);
@@ -579,10 +686,11 @@ public class ConcurrentLinkedQueue extends AbstractQueue
throws java.io.IOException, ClassNotFoundException {
// Read in capacity, and any hidden stuff
s.defaultReadObject();
- head = new Node(null, null);
+ head = new Node(null);
tail = head;
// Read in all elements and place in queue
for (;;) {
+ @SuppressWarnings("unchecked")
E item = (E)s.readObject();
if (item == null)
break;
@@ -591,4 +699,35 @@ public class ConcurrentLinkedQueue extends AbstractQueue
}
}
+ // Unsafe mechanics
+
+ private static final sun.misc.Unsafe UNSAFE = sun.misc.Unsafe.getUnsafe();
+ private static final long headOffset =
+ objectFieldOffset(UNSAFE, "head", ConcurrentLinkedQueue.class);
+ private static final long tailOffset =
+ objectFieldOffset(UNSAFE, "tail", ConcurrentLinkedQueue.class);
+
+ private boolean casTail(Node cmp, Node val) {
+ return UNSAFE.compareAndSwapObject(this, tailOffset, cmp, val);
+ }
+
+ private boolean casHead(Node cmp, Node val) {
+ return UNSAFE.compareAndSwapObject(this, headOffset, cmp, val);
+ }
+
+ private void lazySetHead(Node val) {
+ UNSAFE.putOrderedObject(this, headOffset, val);
+ }
+
+ static long objectFieldOffset(sun.misc.Unsafe UNSAFE,
+ String field, Class> klazz) {
+ try {
+ return UNSAFE.objectFieldOffset(klazz.getDeclaredField(field));
+ } catch (NoSuchFieldException e) {
+ // Convert Exception to corresponding Error
+ NoSuchFieldError error = new NoSuchFieldError(field);
+ error.initCause(e);
+ throw error;
+ }
+ }
}
diff --git a/src/share/classes/java/util/concurrent/LinkedBlockingDeque.java b/src/share/classes/java/util/concurrent/LinkedBlockingDeque.java
index 48fc8717a42193ed75e45dd7335906307eaa6e7c..dd34d0dc6b72af2f4e523a4bf50ddbb03363f60a 100644
--- a/src/share/classes/java/util/concurrent/LinkedBlockingDeque.java
+++ b/src/share/classes/java/util/concurrent/LinkedBlockingDeque.java
@@ -34,8 +34,13 @@
*/
package java.util.concurrent;
-import java.util.*;
-import java.util.concurrent.locks.*;
+
+import java.util.AbstractQueue;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+import java.util.concurrent.locks.Condition;
+import java.util.concurrent.locks.ReentrantLock;
/**
* An optionally-bounded {@linkplain BlockingDeque blocking deque} based on
@@ -73,6 +78,20 @@ public class LinkedBlockingDeque
/*
* Implemented as a simple doubly-linked list protected by a
* single lock and using conditions to manage blocking.
+ *
+ * To implement weakly consistent iterators, it appears we need to
+ * keep all Nodes GC-reachable from a predecessor dequeued Node.
+ * That would cause two problems:
+ * - allow a rogue Iterator to cause unbounded memory retention
+ * - cause cross-generational linking of old Nodes to new Nodes if
+ * a Node was tenured while live, which generational GCs have a
+ * hard time dealing with, causing repeated major collections.
+ * However, only non-deleted Nodes need to be reachable from
+ * dequeued Nodes, and reachability does not necessarily have to
+ * be of the kind understood by the GC. We use the trick of
+ * linking a Node that has just been dequeued to itself. Such a
+ * self-link implicitly means to jump to "first" (for next links)
+ * or "last" (for prev links).
*/
/*
@@ -86,9 +105,27 @@ public class LinkedBlockingDeque
/** Doubly-linked list node class */
static final class Node {
+ /**
+ * The item, or null if this node has been removed.
+ */
E item;
+
+ /**
+ * One of:
+ * - the real predecessor Node
+ * - this Node, meaning the predecessor is tail
+ * - null, meaning there is no predecessor
+ */
Node prev;
+
+ /**
+ * One of:
+ * - the real successor Node
+ * - this Node, meaning the successor is head
+ * - null, meaning there is no successor
+ */
Node next;
+
Node(E x, Node p, Node n) {
item = x;
prev = p;
@@ -96,23 +133,37 @@ public class LinkedBlockingDeque
}
}
- /** Pointer to first node */
- private transient Node first;
- /** Pointer to last node */
- private transient Node last;
+ /**
+ * Pointer to first node.
+ * Invariant: (first == null && last == null) ||
+ * (first.prev == null && first.item != null)
+ */
+ transient Node first;
+
+ /**
+ * Pointer to last node.
+ * Invariant: (first == null && last == null) ||
+ * (last.next == null && last.item != null)
+ */
+ transient Node last;
+
/** Number of items in the deque */
private transient int count;
+
/** Maximum number of items in the deque */
private final int capacity;
+
/** Main lock guarding all access */
- private final ReentrantLock lock = new ReentrantLock();
+ final ReentrantLock lock = new ReentrantLock();
+
/** Condition for waiting takes */
private final Condition notEmpty = lock.newCondition();
+
/** Condition for waiting puts */
private final Condition notFull = lock.newCondition();
/**
- * Creates a LinkedBlockingDeque with a capacity of
+ * Creates a {@code LinkedBlockingDeque} with a capacity of
* {@link Integer#MAX_VALUE}.
*/
public LinkedBlockingDeque() {
@@ -120,10 +171,10 @@ public class LinkedBlockingDeque
}
/**
- * Creates a LinkedBlockingDeque with the given (fixed) capacity.
+ * Creates a {@code LinkedBlockingDeque} with the given (fixed) capacity.
*
* @param capacity the capacity of this deque
- * @throws IllegalArgumentException if capacity is less than 1
+ * @throws IllegalArgumentException if {@code capacity} is less than 1
*/
public LinkedBlockingDeque(int capacity) {
if (capacity <= 0) throw new IllegalArgumentException();
@@ -131,7 +182,7 @@ public class LinkedBlockingDeque
}
/**
- * Creates a LinkedBlockingDeque with a capacity of
+ * Creates a {@code LinkedBlockingDeque} with a capacity of
* {@link Integer#MAX_VALUE}, initially containing the elements of
* the given collection, added in traversal order of the
* collection's iterator.
@@ -142,8 +193,18 @@ public class LinkedBlockingDeque
*/
public LinkedBlockingDeque(Collection extends E> c) {
this(Integer.MAX_VALUE);
- for (E e : c)
- add(e);
+ final ReentrantLock lock = this.lock;
+ lock.lock(); // Never contended, but necessary for visibility
+ try {
+ for (E e : c) {
+ if (e == null)
+ throw new NullPointerException();
+ if (!linkLast(e))
+ throw new IllegalStateException("Deque full");
+ }
+ } finally {
+ lock.unlock();
+ }
}
@@ -153,9 +214,9 @@ public class LinkedBlockingDeque
* Links e as first element, or returns false if full.
*/
private boolean linkFirst(E e) {
+ // assert lock.isHeldByCurrentThread();
if (count >= capacity)
return false;
- ++count;
Node f = first;
Node x = new Node(e, null, f);
first = x;
@@ -163,6 +224,7 @@ public class LinkedBlockingDeque
last = x;
else
f.prev = x;
+ ++count;
notEmpty.signal();
return true;
}
@@ -171,9 +233,9 @@ public class LinkedBlockingDeque
* Links e as last element, or returns false if full.
*/
private boolean linkLast(E e) {
+ // assert lock.isHeldByCurrentThread();
if (count >= capacity)
return false;
- ++count;
Node l = last;
Node x = new Node(e, l, null);
last = x;
@@ -181,6 +243,7 @@ public class LinkedBlockingDeque
first = x;
else
l.next = x;
+ ++count;
notEmpty.signal();
return true;
}
@@ -189,10 +252,14 @@ public class LinkedBlockingDeque
* Removes and returns first element, or null if empty.
*/
private E unlinkFirst() {
+ // assert lock.isHeldByCurrentThread();
Node f = first;
if (f == null)
return null;
Node n = f.next;
+ E item = f.item;
+ f.item = null;
+ f.next = f; // help GC
first = n;
if (n == null)
last = null;
@@ -200,17 +267,21 @@ public class LinkedBlockingDeque
n.prev = null;
--count;
notFull.signal();
- return f.item;
+ return item;
}
/**
* Removes and returns last element, or null if empty.
*/
private E unlinkLast() {
+ // assert lock.isHeldByCurrentThread();
Node l = last;
if (l == null)
return null;
Node p = l.prev;
+ E item = l.item;
+ l.item = null;
+ l.prev = l; // help GC
last = p;
if (p == null)
first = null;
@@ -218,31 +289,29 @@ public class LinkedBlockingDeque
p.next = null;
--count;
notFull.signal();
- return l.item;
+ return item;
}
/**
- * Unlink e
+ * Unlinks x.
*/
- private void unlink(Node x) {
+ void unlink(Node x) {
+ // assert lock.isHeldByCurrentThread();
Node p = x.prev;
Node n = x.next;
if (p == null) {
- if (n == null)
- first = last = null;
- else {
- n.prev = null;
- first = n;
- }
+ unlinkFirst();
} else if (n == null) {
- p.next = null;
- last = p;
+ unlinkLast();
} else {
p.next = n;
n.prev = p;
+ x.item = null;
+ // Don't mess with x's links. They may still be in use by
+ // an iterator.
+ --count;
+ notFull.signal();
}
- --count;
- notFull.signalAll();
}
// BlockingDeque methods
@@ -270,6 +339,7 @@ public class LinkedBlockingDeque
*/
public boolean offerFirst(E e) {
if (e == null) throw new NullPointerException();
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
return linkFirst(e);
@@ -283,6 +353,7 @@ public class LinkedBlockingDeque
*/
public boolean offerLast(E e) {
if (e == null) throw new NullPointerException();
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
return linkLast(e);
@@ -297,6 +368,7 @@ public class LinkedBlockingDeque
*/
public void putFirst(E e) throws InterruptedException {
if (e == null) throw new NullPointerException();
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
while (!linkFirst(e))
@@ -312,6 +384,7 @@ public class LinkedBlockingDeque
*/
public void putLast(E e) throws InterruptedException {
if (e == null) throw new NullPointerException();
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
while (!linkLast(e))
@@ -329,15 +402,15 @@ public class LinkedBlockingDeque
throws InterruptedException {
if (e == null) throw new NullPointerException();
long nanos = unit.toNanos(timeout);
+ final ReentrantLock lock = this.lock;
lock.lockInterruptibly();
try {
- for (;;) {
- if (linkFirst(e))
- return true;
+ while (!linkFirst(e)) {
if (nanos <= 0)
return false;
nanos = notFull.awaitNanos(nanos);
}
+ return true;
} finally {
lock.unlock();
}
@@ -351,15 +424,15 @@ public class LinkedBlockingDeque
throws InterruptedException {
if (e == null) throw new NullPointerException();
long nanos = unit.toNanos(timeout);
+ final ReentrantLock lock = this.lock;
lock.lockInterruptibly();
try {
- for (;;) {
- if (linkLast(e))
- return true;
+ while (!linkLast(e)) {
if (nanos <= 0)
return false;
nanos = notFull.awaitNanos(nanos);
}
+ return true;
} finally {
lock.unlock();
}
@@ -384,6 +457,7 @@ public class LinkedBlockingDeque
}
public E pollFirst() {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
return unlinkFirst();
@@ -393,6 +467,7 @@ public class LinkedBlockingDeque
}
public E pollLast() {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
return unlinkLast();
@@ -402,6 +477,7 @@ public class LinkedBlockingDeque
}
public E takeFirst() throws InterruptedException {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
E x;
@@ -414,6 +490,7 @@ public class LinkedBlockingDeque
}
public E takeLast() throws InterruptedException {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
E x;
@@ -428,16 +505,16 @@ public class LinkedBlockingDeque
public E pollFirst(long timeout, TimeUnit unit)
throws InterruptedException {
long nanos = unit.toNanos(timeout);
+ final ReentrantLock lock = this.lock;
lock.lockInterruptibly();
try {
- for (;;) {
- E x = unlinkFirst();
- if (x != null)
- return x;
+ E x;
+ while ( (x = unlinkFirst()) == null) {
if (nanos <= 0)
return null;
nanos = notEmpty.awaitNanos(nanos);
}
+ return x;
} finally {
lock.unlock();
}
@@ -446,16 +523,16 @@ public class LinkedBlockingDeque
public E pollLast(long timeout, TimeUnit unit)
throws InterruptedException {
long nanos = unit.toNanos(timeout);
+ final ReentrantLock lock = this.lock;
lock.lockInterruptibly();
try {
- for (;;) {
- E x = unlinkLast();
- if (x != null)
- return x;
+ E x;
+ while ( (x = unlinkLast()) == null) {
if (nanos <= 0)
return null;
nanos = notEmpty.awaitNanos(nanos);
}
+ return x;
} finally {
lock.unlock();
}
@@ -480,6 +557,7 @@ public class LinkedBlockingDeque
}
public E peekFirst() {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
return (first == null) ? null : first.item;
@@ -489,6 +567,7 @@ public class LinkedBlockingDeque
}
public E peekLast() {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
return (last == null) ? null : last.item;
@@ -499,6 +578,7 @@ public class LinkedBlockingDeque
public boolean removeFirstOccurrence(Object o) {
if (o == null) return false;
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
for (Node p = first; p != null; p = p.next) {
@@ -515,6 +595,7 @@ public class LinkedBlockingDeque
public boolean removeLastOccurrence(Object o) {
if (o == null) return false;
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
for (Node p = last; p != null; p = p.prev) {
@@ -619,14 +700,15 @@ public class LinkedBlockingDeque
* Returns the number of additional elements that this deque can ideally
* (in the absence of memory or resource constraints) accept without
* blocking. This is always equal to the initial capacity of this deque
- * less the current size of this deque.
+ * less the current {@code size} of this deque.
*
* Note that you cannot always tell if an attempt to insert
- * an element will succeed by inspecting remainingCapacity
+ * an element will succeed by inspecting {@code remainingCapacity}
* because it may be the case that another thread is about to
* insert or remove an element.
*/
public int remainingCapacity() {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
return capacity - count;
@@ -642,22 +724,7 @@ public class LinkedBlockingDeque
* @throws IllegalArgumentException {@inheritDoc}
*/
public int drainTo(Collection super E> c) {
- if (c == null)
- throw new NullPointerException();
- if (c == this)
- throw new IllegalArgumentException();
- lock.lock();
- try {
- for (Node p = first; p != null; p = p.next)
- c.add(p.item);
- int n = count;
- count = 0;
- first = last = null;
- notFull.signalAll();
- return n;
- } finally {
- lock.unlock();
- }
+ return drainTo(c, Integer.MAX_VALUE);
}
/**
@@ -671,19 +738,14 @@ public class LinkedBlockingDeque
throw new NullPointerException();
if (c == this)
throw new IllegalArgumentException();
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
- int n = 0;
- while (n < maxElements && first != null) {
- c.add(first.item);
- first.prev = null;
- first = first.next;
- --count;
- ++n;
+ int n = Math.min(maxElements, count);
+ for (int i = 0; i < n; i++) {
+ c.add(first.item); // In this order, in case add() throws.
+ unlinkFirst();
}
- if (first == null)
- last = null;
- notFull.signalAll();
return n;
} finally {
lock.unlock();
@@ -712,16 +774,16 @@ public class LinkedBlockingDeque
/**
* Removes the first occurrence of the specified element from this deque.
* If the deque does not contain the element, it is unchanged.
- * More formally, removes the first element e such that
- * o.equals(e) (if such an element exists).
- * Returns true if this deque contained the specified element
+ * More formally, removes the first element {@code e} such that
+ * {@code o.equals(e)} (if such an element exists).
+ * Returns {@code true} if this deque contained the specified element
* (or equivalently, if this deque changed as a result of the call).
*
* This method is equivalent to
* {@link #removeFirstOccurrence(Object) removeFirstOccurrence}.
*
* @param o element to be removed from this deque, if present
- * @return true if this deque changed as a result of the call
+ * @return {@code true} if this deque changed as a result of the call
*/
public boolean remove(Object o) {
return removeFirstOccurrence(o);
@@ -733,6 +795,7 @@ public class LinkedBlockingDeque
* @return the number of elements in this deque
*/
public int size() {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
return count;
@@ -742,15 +805,16 @@ public class LinkedBlockingDeque
}
/**
- * Returns true if this deque contains the specified element.
- * More formally, returns true if and only if this deque contains
- * at least one element e such that o.equals(e) .
+ * Returns {@code true} if this deque contains the specified element.
+ * More formally, returns {@code true} if and only if this deque contains
+ * at least one element {@code e} such that {@code o.equals(e)}.
*
* @param o object to be checked for containment in this deque
- * @return true if this deque contains the specified element
+ * @return {@code true} if this deque contains the specified element
*/
public boolean contains(Object o) {
if (o == null) return false;
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
for (Node p = first; p != null; p = p.next)
@@ -762,24 +826,46 @@ public class LinkedBlockingDeque
}
}
- /**
- * Variant of removeFirstOccurrence needed by iterator.remove.
- * Searches for the node, not its contents.
+ /*
+ * TODO: Add support for more efficient bulk operations.
+ *
+ * We don't want to acquire the lock for every iteration, but we
+ * also want other threads a chance to interact with the
+ * collection, especially when count is close to capacity.
*/
- boolean removeNode(Node e) {
- lock.lock();
- try {
- for (Node p = first; p != null; p = p.next) {
- if (p == e) {
- unlink(p);
- return true;
- }
- }
- return false;
- } finally {
- lock.unlock();
- }
- }
+
+// /**
+// * Adds all of the elements in the specified collection to this
+// * queue. Attempts to addAll of a queue to itself result in
+// * {@code IllegalArgumentException}. Further, the behavior of
+// * this operation is undefined if the specified collection is
+// * modified while the operation is in progress.
+// *
+// * @param c collection containing elements to be added to this queue
+// * @return {@code true} if this queue changed as a result of the call
+// * @throws ClassCastException {@inheritDoc}
+// * @throws NullPointerException {@inheritDoc}
+// * @throws IllegalArgumentException {@inheritDoc}
+// * @throws IllegalStateException {@inheritDoc}
+// * @see #add(Object)
+// */
+// public boolean addAll(Collection extends E> c) {
+// if (c == null)
+// throw new NullPointerException();
+// if (c == this)
+// throw new IllegalArgumentException();
+// final ReentrantLock lock = this.lock;
+// lock.lock();
+// try {
+// boolean modified = false;
+// for (E e : c)
+// if (linkLast(e))
+// modified = true;
+// return modified;
+// } finally {
+// lock.unlock();
+// }
+// }
/**
* Returns an array containing all of the elements in this deque, in
@@ -794,7 +880,9 @@ public class LinkedBlockingDeque
*
* @return an array containing all of the elements in this deque
*/
+ @SuppressWarnings("unchecked")
public Object[] toArray() {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
Object[] a = new Object[count];
@@ -817,22 +905,22 @@ public class LinkedBlockingDeque
* If this deque fits in the specified array with room to spare
* (i.e., the array has more elements than this deque), the element in
* the array immediately following the end of the deque is set to
- * null .
+ * {@code null}.
*
*
Like the {@link #toArray()} method, this method acts as bridge between
* array-based and collection-based APIs. Further, this method allows
* precise control over the runtime type of the output array, and may,
* under certain circumstances, be used to save allocation costs.
*
- *
Suppose x is a deque known to contain only strings.
+ *
Suppose {@code x} is a deque known to contain only strings.
* The following code can be used to dump the deque into a newly
- * allocated array of String :
+ * allocated array of {@code String}:
*
*
* String[] y = x.toArray(new String[0]);
*
- * Note that toArray(new Object[0]) is identical in function to
- * toArray() .
+ * Note that {@code toArray(new Object[0])} is identical in function to
+ * {@code toArray()}.
*
* @param a the array into which the elements of the deque are to
* be stored, if it is big enough; otherwise, a new array of the
@@ -843,14 +931,14 @@ public class LinkedBlockingDeque
* this deque
* @throws NullPointerException if the specified array is null
*/
+ @SuppressWarnings("unchecked")
public T[] toArray(T[] a) {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
if (a.length < count)
- a = (T[])java.lang.reflect.Array.newInstance(
- a.getClass().getComponentType(),
- count
- );
+ a = (T[])java.lang.reflect.Array.newInstance
+ (a.getClass().getComponentType(), count);
int k = 0;
for (Node p = first; p != null; p = p.next)
@@ -864,6 +952,7 @@ public class LinkedBlockingDeque
}
public String toString() {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
return super.toString();
@@ -877,8 +966,16 @@ public class LinkedBlockingDeque
* The deque will be empty after this call returns.
*/
public void clear() {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
+ for (Node f = first; f != null; ) {
+ f.item = null;
+ Node n = f.next;
+ f.prev = null;
+ f.next = null;
+ f = n;
+ }
first = last = null;
count = 0;
notFull.signalAll();
@@ -890,8 +987,9 @@ public class LinkedBlockingDeque
/**
* Returns an iterator over the elements in this deque in proper sequence.
* The elements will be returned in order from first (head) to last (tail).
- * The returned Iterator is a "weakly consistent" iterator that
- * will never throw {@link ConcurrentModificationException},
+ * The returned {@code Iterator} is a "weakly consistent" iterator that
+ * will never throw {@link java.util.ConcurrentModificationException
+ * ConcurrentModificationException},
* and guarantees to traverse elements as they existed upon
* construction of the iterator, and may (but is not guaranteed to)
* reflect any modifications subsequent to construction.
@@ -906,8 +1004,9 @@ public class LinkedBlockingDeque
* Returns an iterator over the elements in this deque in reverse
* sequential order. The elements will be returned in order from
* last (tail) to first (head).
- * The returned Iterator is a "weakly consistent" iterator that
- * will never throw {@link ConcurrentModificationException},
+ * The returned {@code Iterator} is a "weakly consistent" iterator that
+ * will never throw {@link java.util.ConcurrentModificationException
+ * ConcurrentModificationException},
* and guarantees to traverse elements as they existed upon
* construction of the iterator, and may (but is not guaranteed to)
* reflect any modifications subsequent to construction.
@@ -921,7 +1020,7 @@ public class LinkedBlockingDeque
*/
private abstract class AbstractItr implements Iterator {
/**
- * The next node to return in next
+ * The next node to return in next()
*/
Node next;
@@ -939,15 +1038,44 @@ public class LinkedBlockingDeque
*/
private Node lastRet;
+ abstract Node firstNode();
+ abstract Node nextNode(Node n);
+
AbstractItr() {
- advance(); // set to initial position
+ // set to initial position
+ final ReentrantLock lock = LinkedBlockingDeque.this.lock;
+ lock.lock();
+ try {
+ next = firstNode();
+ nextItem = (next == null) ? null : next.item;
+ } finally {
+ lock.unlock();
+ }
}
/**
- * Advances next, or if not yet initialized, sets to first node.
- * Implemented to move forward vs backward in the two subclasses.
+ * Advances next.
*/
- abstract void advance();
+ void advance() {
+ final ReentrantLock lock = LinkedBlockingDeque.this.lock;
+ lock.lock();
+ try {
+ // assert next != null;
+ Node s = nextNode(next);
+ if (s == next) {
+ next = firstNode();
+ } else {
+ // Skip over removed nodes.
+ // May be necessary if multiple interior Nodes are removed.
+ while (s != null && s.item == null)
+ s = nextNode(s);
+ next = s;
+ }
+ nextItem = (next == null) ? null : next.item;
+ } finally {
+ lock.unlock();
+ }
+ }
public boolean hasNext() {
return next != null;
@@ -967,52 +1095,39 @@ public class LinkedBlockingDeque
if (n == null)
throw new IllegalStateException();
lastRet = null;
- // Note: removeNode rescans looking for this node to make
- // sure it was not already removed. Otherwise, trying to
- // re-remove could corrupt list.
- removeNode(n);
- }
- }
-
- /** Forward iterator */
- private class Itr extends AbstractItr {
- void advance() {
final ReentrantLock lock = LinkedBlockingDeque.this.lock;
lock.lock();
try {
- next = (next == null)? first : next.next;
- nextItem = (next == null)? null : next.item;
+ if (n.item != null)
+ unlink(n);
} finally {
lock.unlock();
}
}
}
- /**
- * Descending iterator for LinkedBlockingDeque
- */
+ /** Forward iterator */
+ private class Itr extends AbstractItr {
+ Node firstNode() { return first; }
+ Node nextNode(Node n) { return n.next; }
+ }
+
+ /** Descending iterator */
private class DescendingItr extends AbstractItr {
- void advance() {
- final ReentrantLock lock = LinkedBlockingDeque.this.lock;
- lock.lock();
- try {
- next = (next == null)? last : next.prev;
- nextItem = (next == null)? null : next.item;
- } finally {
- lock.unlock();
- }
- }
+ Node firstNode() { return last; }
+ Node nextNode(Node n) { return n.prev; }
}
/**
* Save the state of this deque to a stream (that is, serialize it).
*
* @serialData The capacity (int), followed by elements (each an
- * Object ) in the proper order, followed by a null
+ * {@code Object}) in the proper order, followed by a null
* @param s the stream
*/
private void writeObject(java.io.ObjectOutputStream s)
throws java.io.IOException {
+ final ReentrantLock lock = this.lock;
lock.lock();
try {
// Write out capacity and any hidden stuff
@@ -1040,6 +1155,7 @@ public class LinkedBlockingDeque
last = null;
// Read in all elements and place in queue
for (;;) {
+ @SuppressWarnings("unchecked")
E item = (E)s.readObject();
if (item == null)
break;
diff --git a/src/share/classes/java/util/concurrent/LinkedBlockingQueue.java b/src/share/classes/java/util/concurrent/LinkedBlockingQueue.java
index dc56a0346654b57a5aada3aadd57abd1ccf56923..10f2b6540cde3cda1602b55220aef3558984a638 100644
--- a/src/share/classes/java/util/concurrent/LinkedBlockingQueue.java
+++ b/src/share/classes/java/util/concurrent/LinkedBlockingQueue.java
@@ -34,9 +34,14 @@
*/
package java.util.concurrent;
-import java.util.concurrent.atomic.*;
-import java.util.concurrent.locks.*;
-import java.util.*;
+
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.locks.Condition;
+import java.util.concurrent.locks.ReentrantLock;
+import java.util.AbstractQueue;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
/**
* An optionally-bounded {@linkplain BlockingQueue blocking queue} based on
@@ -86,15 +91,43 @@ public class LinkedBlockingQueue