6934265: Add public method Character.isBmpCodePoint

Summary: Move isBmpCodePoint from sun.nio.cs.Surrogate to Character
Reviewed-by: sherman
Contributed-by: NUlf Zibis <ulf.zibis@gmx.de>

src/share/classes/java/lang/AbstractStringBuilder.java

@@ -721,19 +721,18 @@ abstract class AbstractStringBuilder implements Appendable, CharSequence {
      * {@code codePoint} isn't a valid Unicode code point
      */
     public AbstractStringBuilder appendCodePoint(int codePoint) {
-        if (!Character.isValidCodePoint(codePoint)) {
-            throw new IllegalArgumentException();
-        }
-        int n = 1;
-        if (codePoint >= Character.MIN_SUPPLEMENTARY_CODE_POINT) {
-            n++;
-        }
-        ensureCapacityInternal(count + n);
-        if (n == 1) {
-            value[count++] = (char) codePoint;
-        } else {
+        final int count = this.count;
+
+        if (Character.isBmpCodePoint(codePoint)) {
+            ensureCapacityInternal(count + 1);
+            value[count] = (char) codePoint;
+            this.count = count + 1;
+        } else if (Character.isValidCodePoint(codePoint)) {
+            ensureCapacityInternal(count + 2);
             Character.toSurrogates(codePoint, value, count);
-            count += n;
+            this.count = count + 2;
+        } else {
+            throw new IllegalArgumentException();
         }
         return this;
     }

src/share/classes/java/lang/Character.java

@@ -67,17 +67,16 @@ import java.util.Locale;
  * definition</i></a> of the U+<i>n</i> notation in the Unicode
  * standard.)
  *
- * <p>The set of characters from U+0000 to U+FFFF is sometimes
- * referred to as the <em>Basic Multilingual Plane (BMP)</em>. <a
- * name="supplementary">Characters</a> whose code points are greater
+ * <p><a name="BMP">The set of characters from U+0000 to U+FFFF is
+ * sometimes referred to as the <em>Basic Multilingual Plane (BMP)</em>.
+ * <a name="supplementary">Characters</a> whose code points are greater
  * than U+FFFF are called <em>supplementary character</em>s.  The Java
- * 2 platform uses the UTF-16 representation in <code>char</code>
- * arrays and in the <code>String</code> and <code>StringBuffer</code>
- * classes. In this representation, supplementary characters are
- * represented as a pair of <code>char</code> values, the first from
- * the <em>high-surrogates</em> range, (&#92;uD800-&#92;uDBFF), the
- * second from the <em>low-surrogates</em> range
- * (&#92;uDC00-&#92;uDFFF).
+ * platform uses the UTF-16 representation in <code>char</code> arrays and
+ * in the <code>String</code> and <code>StringBuffer</code> classes. In
+ * this representation, supplementary characters are represented as a pair
+ * of <code>char</code> values, the first from the <em>high-surrogates</em>
+ * range, (&#92;uD800-&#92;uDBFF), the second from the
+ * <em>low-surrogates</em> range (&#92;uDC00-&#92;uDFFF).
  *
  * <p>A <code>char</code> value, therefore, represents Basic
  * Multilingual Plane (BMP) code points, including the surrogate
@@ -3922,6 +3921,25 @@ class Character extends Object implements java.io.Serializable, Comparable<Chara
         return plane < ((MAX_CODE_POINT + 1) >>> 16);
     }
 
+    /**
+     * Determines whether the specified character (Unicode code point)
+     * is in the <a href="#BMP">Basic Multilingual Plane (BMP)</a>.
+     * Such code points can be represented using a single {@code char}.
+     *
+     * @param  codePoint the character (Unicode code point) to be tested
+     * @return {@code true} if the specified code point is between
+     *         {@link #MIN_VALUE} and {@link #MAX_VALUE} inclusive;
+     *         {@code false} otherwise.
+     * @since  1.7
+     */
+    public static boolean isBmpCodePoint(int codePoint) {
+        return codePoint >>> 16 == 0;
+        // Optimized form of:
+        //     codePoint >= MIN_VALUE && codePoint <= MAX_VALUE
+        // We consistently use logical shift (>>>) to facilitate
+        // additional runtime optimizations.
+    }
+
     /**
      * Determines whether the specified character (Unicode code point)
      * is in the <a href="#supplementary">supplementary character</a> range.
@@ -4319,15 +4337,15 @@ class Character extends Object implements java.io.Serializable, Comparable<Chara
      * @since  1.5
      */
     public static int toChars(int codePoint, char[] dst, int dstIndex) {
-        if (codePoint < 0 || codePoint > MAX_CODE_POINT) {
-            throw new IllegalArgumentException();
-        }
-        if (codePoint < MIN_SUPPLEMENTARY_CODE_POINT) {
+        if (isBmpCodePoint(codePoint)) {
             dst[dstIndex] = (char) codePoint;
             return 1;
+        } else if (isValidCodePoint(codePoint)) {
+            toSurrogates(codePoint, dst, dstIndex);
+            return 2;
+        } else {
+            throw new IllegalArgumentException();
         }
-        toSurrogates(codePoint, dst, dstIndex);
-        return 2;
     }
 
     /**
@@ -4347,15 +4365,15 @@ class Character extends Object implements java.io.Serializable, Comparable<Chara
      * @since  1.5
      */
     public static char[] toChars(int codePoint) {
-        if (codePoint < 0 || codePoint > MAX_CODE_POINT) {
+        if (isBmpCodePoint(codePoint)) {
+            return new char[] { (char) codePoint };
+        } else if (isValidCodePoint(codePoint)) {
+            char[] result = new char[2];
+            toSurrogates(codePoint, result, 0);
+            return result;
+        } else {
             throw new IllegalArgumentException();
         }
-        if (codePoint < MIN_SUPPLEMENTARY_CODE_POINT) {
-                return new char[] { (char) codePoint };
-        }
-        char[] result = new char[2];
-        toSurrogates(codePoint, result, 0);
-        return result;
     }
 
     static void toSurrogates(int codePoint, char[] dst, int index) {
@@ -6259,8 +6277,7 @@ class Character extends Object implements java.io.Serializable, Comparable<Chara
      */
     static char[] toUpperCaseCharArray(int codePoint) {
         // As of Unicode 4.0, 1:M uppercasings only happen in the BMP.
-        assert isValidCodePoint(codePoint) &&
-               !isSupplementaryCodePoint(codePoint);
+        assert isBmpCodePoint(codePoint);
         return CharacterData.of(codePoint).toUpperCaseCharArray(codePoint);
     }
 

src/share/classes/java/lang/String.java

@@ -99,6 +99,8 @@ import java.util.regex.PatternSyntaxException;
  *
  * @author  Lee Boynton
  * @author  Arthur van Hoff
+ * @author  Martin Buchholz
+ * @author  Ulf Zibis
  * @see     java.lang.Object#toString()
  * @see     java.lang.StringBuffer
  * @see     java.lang.StringBuilder
@@ -273,32 +275,32 @@ public final class String
             throw new StringIndexOutOfBoundsException(offset + count);
         }
 
+        final int end = offset + count;
+
         // Pass 1: Compute precise size of char[]
-        int n = 0;
-        for (int i = offset; i < offset + count; i++) {
+        int n = count;
+        for (int i = offset; i < end; i++) {
             int c = codePoints[i];
-            if (c >= Character.MIN_CODE_POINT &&
-                c <  Character.MIN_SUPPLEMENTARY_CODE_POINT)
-                n += 1;
-            else if (Character.isSupplementaryCodePoint(c))
-                n += 2;
+            if (Character.isBmpCodePoint(c))
+                continue;
+            else if (Character.isValidCodePoint(c))
+                n++;
             else throw new IllegalArgumentException(Integer.toString(c));
         }
 
         // Pass 2: Allocate and fill in char[]
-        char[] v = new char[n];
-        for (int i = offset, j = 0; i < offset + count; i++) {
+        final char[] v = new char[n];
+
+        for (int i = offset, j = 0; i < end; i++, j++) {
             int c = codePoints[i];
-            if (c < Character.MIN_SUPPLEMENTARY_CODE_POINT) {
-                v[j++] = (char) c;
-            } else {
-                Character.toSurrogates(c, v, j);
-                j += 2;
-            }
+            if (Character.isBmpCodePoint(c))
+                v[j] = (char) c;
+            else
+                Character.toSurrogates(c, v, j++);
         }
 
         this.value  = v;
-        this.count  = v.length;
+        this.count  = n;
         this.offset = 0;
     }
 

src/share/classes/sun/io/CharToByteDBCS_ASCII.java

@@ -24,7 +24,6 @@
  */
 package sun.io;
 
-import sun.nio.cs.Surrogate;
 import sun.nio.cs.ext.DoubleByte;
 import static sun.nio.cs.CharsetMapping.*;
 

src/share/classes/sun/io/CharToByteDBCS_EBCDIC.java

@@ -24,7 +24,6 @@
  */
 package sun.io;
 
-import sun.nio.cs.Surrogate;
 import sun.nio.cs.ext.DoubleByte;
 import static sun.nio.cs.CharsetMapping.*;
 

src/share/classes/sun/nio/cs/Surrogate.java

 /*
- * Copyright (c) 2000, 2001, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2010, Oracle and/or its affiliates. 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
@@ -34,8 +34,9 @@ import java.nio.charset.UnmappableCharacterException;
  * Utility class for dealing with surrogates.
  *
  * @author Mark Reinhold
+ * @author Martin Buchholz
+ * @author Ulf Zibis
  */
-
 public class Surrogate {
 
     private Surrogate() { }
@@ -74,17 +75,10 @@ public class Surrogate {
         return (MIN <= c) && (c <= MAX);
     }
 
-    /**
-     * Tells whether or not the given UCS-4 character is in the Basic
-     * Multilingual Plane, and can be represented using a single char.
-     */
-    public static boolean isBMPCodePoint(int uc) {
-        return uc >> 16 == 0;
-    }
-
     /**
      * Tells whether or not the given UCS-4 character must be represented as a
      * surrogate pair in UTF-16.
+     * Use of {@link Character#isSupplementaryCodePoint} is generally preferred.
      */
     public static boolean neededFor(int uc) {
         return Character.isSupplementaryCodePoint(uc);
@@ -110,6 +104,7 @@ public class Surrogate {
 
     /**
      * Converts the given surrogate pair into a 32-bit UCS-4 character.
+     * Use of {@link Character#toCodePoint} is generally preferred.
      */
     public static int toUCS4(char c, char d) {
         assert Character.isHighSurrogate(c) && Character.isLowSurrogate(d);
@@ -290,8 +285,9 @@ public class Surrogate {
          *           error() will return a descriptive result object
          */
         public int generate(int uc, int len, CharBuffer dst) {
-            if (Surrogate.isBMPCodePoint(uc)) {
-                if (Surrogate.is(uc)) {
+            if (Character.isBmpCodePoint(uc)) {
+                char c = (char) uc;
+                if (Character.isSurrogate(c)) {
                     error = CoderResult.malformedForLength(len);
                     return -1;
                 }
@@ -299,10 +295,10 @@ public class Surrogate {
                     error = CoderResult.OVERFLOW;
                     return -1;
                 }
-                dst.put((char)uc);
+                dst.put(c);
                 error = null;
                 return 1;
-            } else if (Character.isSupplementaryCodePoint(uc)) {
+            } else if (Character.isValidCodePoint(uc)) {
                 if (dst.remaining() < 2) {
                     error = CoderResult.OVERFLOW;
                     return -1;
@@ -334,8 +330,9 @@ public class Surrogate {
          *           error() will return a descriptive result object
          */
         public int generate(int uc, int len, char[] da, int dp, int dl) {
-            if (Surrogate.isBMPCodePoint(uc)) {
-                if (Surrogate.is(uc)) {
+            if (Character.isBmpCodePoint(uc)) {
+                char c = (char) uc;
+                if (Character.isSurrogate(c)) {
                     error = CoderResult.malformedForLength(len);
                     return -1;
                 }
@@ -343,10 +340,10 @@ public class Surrogate {
                     error = CoderResult.OVERFLOW;
                     return -1;
                 }
-                da[dp] = (char)uc;
+                da[dp] = c;
                 error = null;
                 return 1;
-            } else if (Character.isSupplementaryCodePoint(uc)) {
+            } else if (Character.isValidCodePoint(uc)) {
                 if (dl - dp < 2) {
                     error = CoderResult.OVERFLOW;
                     return -1;

src/share/classes/sun/nio/cs/UTF_32Coder.java

@@ -86,22 +86,21 @@ class UTF_32Coder {
                         src.position(mark);
                     }
                 }
-                while (src.remaining() > 3) {
+                while (src.remaining() >= 4) {
                     cp = getCP(src);
-                    if (cp < 0 || cp > Surrogate.UCS4_MAX) {
-                        return CoderResult.malformedForLength(4);
-                    }
-                    if (cp < Surrogate.UCS4_MIN) {
+                    if (Character.isBmpCodePoint(cp)) {
                         if (!dst.hasRemaining())
                             return CoderResult.OVERFLOW;
                         mark += 4;
-                        dst.put((char)cp);
-                    } else {
+                        dst.put((char) cp);
+                    } else if (Character.isValidCodePoint(cp)) {
                         if (dst.remaining() < 2)
                             return CoderResult.OVERFLOW;
                         mark += 4;
                         dst.put(Surrogate.high(cp));
                         dst.put(Surrogate.low(cp));
+                    } else {
+                        return CoderResult.malformedForLength(4);
                     }
                 }
                 return CoderResult.UNDERFLOW;
@@ -154,7 +153,12 @@ class UTF_32Coder {
             try {
                 while (src.hasRemaining()) {
                     char c = src.get();
-                    if (Character.isHighSurrogate(c)) {
+                    if (!Character.isSurrogate(c)) {
+                        if (dst.remaining() < 4)
+                            return CoderResult.OVERFLOW;
+                        mark++;
+                        put(c, dst);
+                    } else if (Character.isHighSurrogate(c)) {
                         if (!src.hasRemaining())
                             return CoderResult.UNDERFLOW;
                         char low = src.get();
@@ -162,17 +166,13 @@ class UTF_32Coder {
                             if (dst.remaining() < 4)
                                 return CoderResult.OVERFLOW;
                             mark += 2;
-                            put(Surrogate.toUCS4(c, low), dst);
+                            put(Character.toCodePoint(c, low), dst);
                         } else {
                             return CoderResult.malformedForLength(1);
                         }
-                    } else if (Character.isLowSurrogate(c)) {
-                        return CoderResult.malformedForLength(1);
                     } else {
-                        if (dst.remaining() < 4)
-                            return CoderResult.OVERFLOW;
-                        mark++;
-                        put(c, dst);
+                        // assert Character.isLowSurrogate(c);
+                        return CoderResult.malformedForLength(1);
                     }
                 }
                 return CoderResult.UNDERFLOW;

src/share/classes/sun/nio/cs/UTF_8.java

@@ -102,7 +102,7 @@ class UTF_8 extends Unicode
         //  [F1..F3] [80..BF] [80..BF] [80..BF]
         //  [F4]     [80..8F] [80..BF] [80..BF]
         //  only check 80-be range here, the [0xf0,0x80...] and [0xf4,0x90-...]
-        //  will be checked by Surrogate.neededFor(uc)
+        //  will be checked by Character.isSupplementaryCodePoint(uc)
         private static boolean isMalformed4(int b2, int b3, int b4) {
             return (b2 & 0xc0) != 0x80 || (b3 & 0xc0) != 0x80 ||
                    (b4 & 0xc0) != 0x80;
@@ -248,7 +248,8 @@ class UTF_8 extends Unicode
                              ((b3 & 0x3f) << 06) |
                              (b4 & 0x3f);
                     if (isMalformed4(b2, b3, b4) ||
-                        !Surrogate.neededFor(uc)) {
+                        // shortest form check
+                        !Character.isSupplementaryCodePoint(uc)) {
                         return malformed(src, sp, dst, dp, 4);
                     }
                     da[dp++] = Surrogate.high(uc);
@@ -304,7 +305,8 @@ class UTF_8 extends Unicode
                              ((b3 & 0x3f) << 06) |
                              (b4 & 0x3f);
                     if (isMalformed4(b2, b3, b4) ||
-                        !Surrogate.neededFor(uc)) { // shortest form check
+                        // shortest form check
+                        !Character.isSupplementaryCodePoint(uc)) {
                         return malformed(src, mark, 4);
                     }
                     dst.put(Surrogate.high(uc));

src/share/classes/sun/nio/cs/ext/EUC_TW.java

@@ -441,7 +441,7 @@ public class EUC_TW extends Charset implements HistoricallyNamedCharset
         }
 
         static int encode(char hi, char low, byte[] bb) {
-            int c = Surrogate.toUCS4(hi, low);
+            int c = Character.toCodePoint(hi, low);
             if ((c & 0xf0000) != 0x20000)
                 return -1;
             c -= 0x20000;

src/share/classes/sun/nio/cs/ext/GB18030.java

@@ -12628,7 +12628,7 @@ public class GB18030
                     if (Character.isSurrogate(c)) {
                         if ((condensedKey=sgp.parse(c, sa, sp, sl)) < 0)
                             return sgp.error();
-                        // Surogate.toUCS4 looks like
+                        // Character.toCodePoint looks like
                         // (((high & 0x3ff) << 10) | (low & 0x3ff)) + 0x10000;
                         // so we add (0x2e248 - 0x10000) to get the "key".
                         condensedKey += 0x1E248;

src/share/classes/sun/nio/cs/ext/IBM33722.java

@@ -36,7 +36,6 @@ import java.nio.charset.CharsetDecoder;
 import java.nio.charset.CharsetEncoder;
 import java.nio.charset.CoderResult;
 import sun.nio.cs.HistoricallyNamedCharset;
-import sun.nio.cs.Surrogate;
 
 public class IBM33722
     extends Charset

src/share/classes/sun/nio/cs/ext/IBM964.java

@@ -36,7 +36,6 @@ import java.nio.charset.CharsetDecoder;
 import java.nio.charset.CharsetEncoder;
 import java.nio.charset.CoderResult;
 import sun.nio.cs.HistoricallyNamedCharset;
-import sun.nio.cs.Surrogate;
 
 public class IBM964
     extends Charset

test/java/nio/charset/coders/BashStreams.java

@@ -46,7 +46,7 @@ public class BashStreams {
 
         CharacterGenerator(long seed, String csn, int limit) {
             rand = new Random(seed);
-            this.max = Surrogate.UCS4_MAX + 1;
+            this.max = Character.MAX_CODE_POINT + 1;
             this.limit = limit;
         }
 
@@ -77,17 +77,20 @@ public class BashStreams {
             int c;
             for (;;) {
                 c = rand.nextInt(max);
-                if (Surrogate.is(c) || (c == 0xfffe) || (c == 0xffff))
+                if ((Character.isBmpCodePoint(c)
+                     && (Character.isSurrogate((char) c)
+                         || (c == 0xfffe) || (c == 0xffff))))
                     continue;
-                if (Surrogate.neededFor(c) && (count == limit - 1))
+                if (Character.isSupplementaryCodePoint(c)
+                        && (count == limit - 1))
                     continue;
                 break;
             }
             count++;
-            if (Surrogate.neededFor(c)) {
+            if (Character.isSupplementaryCodePoint(c)) {
                 count++;
-                push(Surrogate.low(c));
-                return Surrogate.high(c);
+                push(sun.nio.cs.Surrogate.low(c));
+                return sun.nio.cs.Surrogate.high(c);
             }
             return (char)c;
         }
@@ -137,7 +140,7 @@ public class BashStreams {
                 char d = cg.next();
                 if (c != d) {
                     if (c == '?') {
-                        if (Surrogate.isHigh(d))
+                        if (Character.isHighSurrogate(d))
                             cg.next();
                         continue;
                     }
@@ -187,7 +190,7 @@ public class BashStreams {
             w.write(ca, 0, n);
             count += n;
         }
-        if (Surrogate.isHigh(ca[n - 1]))
+        if (Character.isHighSurrogate(ca[n - 1]))
             w.write(cg.next());
         w.close();
     }
@@ -253,7 +256,8 @@ public class BashStreams {
                         if (!cg.hasNext())
                             break;
                         char c = cg.next();
-                        if (Surrogate.isHigh(c) && (cb.remaining() == 1)) {
+                        if (Character.isHighSurrogate(c)
+                                && cb.remaining() == 1) {
                             cg.push(c);
                             break;
                         }
@@ -311,7 +315,7 @@ public class BashStreams {
                     mismatchedEOF(csn, count + i, cg.count());
                 char d = cg.next();
                 if (c == '?') {
-                    if (Surrogate.isHigh(d)) {
+                    if (Character.isHighSurrogate(d)) {
                         cg.next();
                         continue;
                     }

test/java/nio/charset/coders/Surrogate.java

-/*
- * Copyright (c) 2010, Oracle and/or its affiliates. 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.
- *
- * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- */
-
-public class Surrogate {
-
-    public static final int UCS4_SURROGATE_MIN = 0x10000;
-    public static final int UCS4_MAX = (1 << 20) + UCS4_SURROGATE_MIN - 1;
-
-    // UTF-16 surrogate-character ranges
-    //
-    public static final char MIN_HIGH = '\uD800';
-    public static final char MAX_HIGH = '\uDBFF';
-    public static final char MIN_LOW  = '\uDC00';
-    public static final char MAX_LOW  = '\uDFFF';
-    public static final char MIN = MIN_HIGH;
-    public static final char MAX = MAX_LOW;
-
-    public static boolean neededFor(int uc) {
-        return (uc >= UCS4_SURROGATE_MIN) && (uc <= UCS4_MAX);
-    }
-
-    public static boolean isHigh(int c) {
-        return (MIN_HIGH <= c) && (c <= MAX_HIGH);
-    }
-
-    static char high(int uc) {
-        return (char)(0xd800 | (((uc - UCS4_SURROGATE_MIN) >> 10) & 0x3ff));
-    }
-
-    public static boolean isLow(int c) {
-        return (MIN_LOW <= c) && (c <= MAX_LOW);
-    }
-
-    static char low(int uc) {
-        return (char)(0xdc00 | ((uc - UCS4_SURROGATE_MIN) & 0x3ff));
-    }
-
-    public static boolean is(int c) {
-        return (MIN <= c) && (c <= MAX);
-    }
-
-    static int toUCS4(char c, char d) {
-        return (((c & 0x3ff) << 10) | (d & 0x3ff)) + 0x10000;
-    }
-
-}

test/java/nio/charset/coders/Surrogates.java

@@ -42,9 +42,8 @@ public class Surrogates {
     static void initData() throws IOException {
         StringBuffer sb = new StringBuffer();
         for (int i = 0; i < LEN; i++) {
-            int c = Surrogate.UCS4_SURROGATE_MIN + 1;
-            sb.append(Surrogate.high(c));
-            sb.append(Surrogate.low(c));
+            int c = Character.MIN_SUPPLEMENTARY_CODE_POINT + 1;
+            sb.append(Character.toChars(c));
         }
         input = sb.toString().toCharArray();
         ByteArrayOutputStream bos = new ByteArrayOutputStream();