8014854: (bf) CharBuffer.chars too slow with default implementation

Reviewed-by: erikj, briangoetz, henryjen, psandoz, mduigou

makefiles/CompileJavaClasses.gmk

@@ -342,7 +342,7 @@ $(eval $(call SetupJavaCompilation,BUILD_JOBJC,\
 		DISABLE_SJAVAC:=true,\
 		SRC:=$(JDK_TOPDIR)/src/macosx/native/jobjc/src/core/java \
 		     $(JDK_TOPDIR)/src/macosx/native/jobjc/src/runtime-additions/java \
-		     $(JDK_OUTPUTDIR)/gensrc, \
+		     $(JDK_OUTPUTDIR)/gensrc_jobjc/src, \
 		INCLUDES := com/apple/jobjc,\
                 EXCLUDES := tests/java/com/apple/jobjc,\
 		BIN:=$(JDK_OUTPUTDIR)/jobjc_classes,\
@@ -355,7 +355,7 @@ $(eval $(call SetupJavaCompilation,BUILD_JOBJC_HEADERS,\
 		SETUP:=GENERATE_JDKBYTECODE,\
 		SRC:=$(JDK_TOPDIR)/src/macosx/native/jobjc/src/core/java \
 		     $(JDK_TOPDIR)/src/macosx/native/jobjc/src/runtime-additions/java \
-		     $(JDK_OUTPUTDIR)/gensrc, \
+		     $(JDK_OUTPUTDIR)/gensrc_jobjc/src, \
 		INCLUDES := com/apple/jobjc,\
                 EXCLUDES := tests/java/com/apple/jobjc,\
 		BIN:=$(JDK_OUTPUTDIR)/jobjc_classes_headers,\

makefiles/GensrcBuffer.gmk

@@ -69,6 +69,9 @@ define typesAndBits
 		$1_fulltype := character
 		$1_Fulltype := Character
 		$1_category := integralType
+                $1_streams  := streamableType
+                $1_streamtype := int
+                $1_Streamtype := Int
 		$1_LBPV     := 1
 	endif
 
@@ -97,7 +100,7 @@ define typesAndBits
 		$1_Type     := Long
 		$1_fulltype := long
 		$1_Fulltype := Long
-		$1_category := integralType
+		$1_category := integralType	
 		$1_LBPV     := 3
 	endif
 
@@ -231,10 +234,13 @@ $$($1_DST) : $$($1_DEP) $(GENSRC_BUFFER_DST)/_the.buffer.dir
 	$(TOOL_SPP) < $$($1_SRC) > $$($1_OUT).tmp \
 		-K$$($1_type) \
 		-K$$($1_category) \
+		-K$$($1_streams) \
 		-Dtype=$$($1_type) \
 		-DType=$$($1_Type) \
 		-Dfulltype=$$($1_fulltype) \
 		-DFulltype=$$($1_Fulltype) \
+                -Dstreamtype=$$($1_streamtype) \
+                -DStreamtype=$$($1_Streamtype) \
 		-Dx=$$($1_x) \
 		-Dmemtype=$$($1_memtype) \
 		-DMemtype=$$($1_Memtype) \

src/share/classes/java/nio/Buffer.java

@@ -25,6 +25,7 @@
 
 package java.nio;
 
+import java.util.Spliterator;
 
 /**
  * A container for data of a specific primitive type.
@@ -173,6 +174,13 @@ package java.nio;
 
 public abstract class Buffer {
 
+    /**
+     * The characteristics of Spliterators that traverse and split elements
+     * maintained in Buffers.
+     */
+    static final int SPLITERATOR_CHARACTERISTICS =
+        Spliterator.SIZED | Spliterator.SUBSIZED | Spliterator.ORDERED;
+
     // Invariants: mark <= position <= limit <= capacity
     private int mark = -1;
     private int position = 0;

src/share/classes/java/nio/ByteBufferAs-X-Buffer.java.template

@@ -115,6 +115,12 @@ class ByteBufferAs$Type$Buffer$RW$$BO$                  // package-private
         return Bits.get$Type$$BO$(bb, ix(checkIndex(i)));
     }
 
+#if[streamableType]
+   $type$ getUnchecked(int i) {
+        return Bits.get$Type$$BO$(bb, ix(i));
+    }
+#end[streamableType]
+
 #end[rw]
 
     public $Type$Buffer put($type$ x) {

src/share/classes/java/nio/CharBufferSpliterator.java

+/*
+ * Copyright (c) 2013, 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.  Oracle designates this
+* particular file as subject to the "Classpath" exception as provided
+ * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package java.nio;
+
+import java.util.Comparator;
+import java.util.Spliterator;
+import java.util.function.IntConsumer;
+
+/**
+ * A Spliterator.OfInt for sources that traverse and split elements
+ * maintained in a CharBuffer.
+ *
+ * @implNote
+ * The implementation is based on the code for the Array-based spliterators.
+ */
+class CharBufferSpliterator implements Spliterator.OfInt {
+    private final CharBuffer buffer;
+    private int index;   // current index, modified on advance/split
+    private final int limit;
+
+    CharBufferSpliterator(CharBuffer buffer) {
+        this(buffer, buffer.position(), buffer.limit());
+    }
+
+    CharBufferSpliterator(CharBuffer buffer, int origin, int limit) {
+        assert origin <= limit;
+        this.buffer = buffer;
+        this.index = (origin <= limit) ? origin : limit;
+        this.limit = limit;
+    }
+
+    @Override
+    public OfInt trySplit() {
+        int lo = index, mid = (lo + limit) >>> 1;
+        return (lo >= mid)
+               ? null
+               : new CharBufferSpliterator(buffer, lo, index = mid);
+    }
+
+    @Override
+    public void forEachRemaining(IntConsumer action) {
+        if (action == null)
+            throw new NullPointerException();
+        CharBuffer cb = buffer;
+        int i = index;
+        int hi = limit;
+        index = hi;
+        while (i < hi) {
+            action.accept(cb.getUnchecked(i++));
+        }
+    }
+
+    @Override
+    public boolean tryAdvance(IntConsumer action) {
+        if (action == null)
+            throw new NullPointerException();
+        if (index >= 0 && index < limit) {
+            action.accept(buffer.getUnchecked(index++));
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public long estimateSize() {
+        return (long)(limit - index);
+    }
+
+    @Override
+    public int characteristics() {
+        return Buffer.SPLITERATOR_CHARACTERISTICS;
+    }
+}

src/share/classes/java/nio/Direct-X-Buffer.java.template

@@ -253,6 +253,12 @@ class Direct$Type$Buffer$RW$$BO$
         return $fromBits$($swap$(unsafe.get$Swaptype$(ix(checkIndex(i)))));
     }
 
+#if[streamableType]
+    $type$ getUnchecked(int i) {
+        return $fromBits$($swap$(unsafe.get$Swaptype$(ix(i))));
+    }
+#end[streamableType]
+
     public $Type$Buffer get($type$[] dst, int offset, int length) {
 #if[rw]
         if ((length << $LG_BYTES_PER_VALUE$) > Bits.JNI_COPY_TO_ARRAY_THRESHOLD) {

src/share/classes/java/nio/Heap-X-Buffer.java.template

@@ -139,6 +139,12 @@ class Heap$Type$Buffer$RW$
         return hb[ix(checkIndex(i))];
     }
 
+#if[streamableType]
+    $type$ getUnchecked(int i) {
+	return hb[ix(i)];
+    }
+#end[streamableType]
+
     public $Type$Buffer get($type$[] dst, int offset, int length) {
         checkBounds(offset, length, dst.length);
         if (length > remaining())

src/share/classes/java/nio/StringCharBuffer.java

@@ -77,6 +77,10 @@ class StringCharBuffer                                  // package-private
         return str.charAt(checkIndex(index) + offset);
     }
 
+    char getUnchecked(int index) {
+        return str.charAt(index + offset);
+    }
+
     // ## Override bulk get methods for better performance
 
     public final CharBuffer put(char c) {

src/share/classes/java/nio/X-Buffer.java.template

@@ -30,6 +30,11 @@ package java.nio;
 #if[char]
 import java.io.IOException;
 #end[char]
+#if[streamableType]
+import java.util.Spliterator;
+import java.util.stream.StreamSupport;
+import java.util.stream.$Streamtype$Stream;
+#end[streamableType]
 
 /**
  * $A$ $type$ buffer.
@@ -589,6 +594,19 @@ public abstract class $Type$Buffer
      */
     public abstract $type$ get(int index);
 
+#if[streamableType]
+    /**
+     * Absolute <i>get</i> method.  Reads the $type$ at the given
+     * index without any validation of the index.
+     *
+     * @param  index
+     *         The index from which the $type$ will be read
+     *
+     * @return  The $type$ at the given index
+     */
+    abstract $type$ getUnchecked(int index);   // package-private
+#end[streamableType]
+
     /**
      * Absolute <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
      *
@@ -1458,4 +1476,16 @@ public abstract class $Type$Buffer
 
 #end[byte]
 
+#if[streamableType]
+
+#if[char]
+    @Override
+#end[char]
+    public $Streamtype$Stream $type$s() {
+        return StreamSupport.$streamtype$Stream(() -> new $Type$BufferSpliterator(this),
+            Buffer.SPLITERATOR_CHARACTERISTICS);
+    }
+
+#end[streamableType]
+
 }

test/java/nio/Buffer/Chars.java

+/*
+ * Copyright (c) 2013, 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.
+ */
+
+/**
+ * @test
+ * @bug 8014854
+ * @summary Exercises CharBuffer#chars on each of the CharBuffer types
+ * @run testng Chars
+ */
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.CharBuffer;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Random;
+
+import org.testng.annotations.DataProvider;
+import org.testng.annotations.Test;
+
+import static org.testng.Assert.assertEquals;
+
+public class Chars {
+
+    static final Random RAND = new Random();
+
+    static final int SIZE = 128 + RAND.nextInt(1024);
+
+    /**
+     * Randomize the char buffer's position and limit.
+     */
+    static CharBuffer randomizeRange(CharBuffer cb) {
+        int mid = cb.capacity() >>> 1;
+        int start = RAND.nextInt(mid);
+        int end = mid + RAND.nextInt(mid);
+        cb.position(start);
+        cb.limit(end);
+        return cb;
+    }
+
+    /**
+     * Randomize the char buffer's contents, position and limit.
+     */
+    static CharBuffer randomize(CharBuffer cb) {
+        while (cb.hasRemaining()) {
+            cb.put((char)RAND.nextInt());
+        }
+        return randomizeRange(cb);
+    }
+
+    /**
+     * Sums the remaining chars in the char buffer.
+     */
+    static int intSum(CharBuffer cb) {
+        int sum = 0;
+        cb.mark();
+        while (cb.hasRemaining()) {
+            sum += cb.get();
+        }
+        cb.reset();
+        return sum;
+    }
+
+    /**
+     * Creates char buffers to test, adding them to the given list.
+     */
+    static void addCases(CharBuffer cb, List<CharBuffer> buffers) {
+        randomize(cb);
+        buffers.add(cb);
+
+        buffers.add(cb.slice());
+        buffers.add(cb.duplicate());
+        buffers.add(cb.asReadOnlyBuffer());
+
+        buffers.add(randomizeRange(cb.slice()));
+        buffers.add(randomizeRange(cb.duplicate()));
+        buffers.add(randomizeRange(cb.asReadOnlyBuffer()));
+    }
+
+    @DataProvider(name = "charbuffers")
+    public Object[][] createCharBuffers() {
+        List<CharBuffer> buffers = new ArrayList<>();
+
+        // heap
+        addCases(CharBuffer.allocate(SIZE), buffers);
+        addCases(CharBuffer.wrap(new char[SIZE]), buffers);
+        addCases(ByteBuffer.allocate(SIZE*2).order(ByteOrder.BIG_ENDIAN).asCharBuffer(),
+                 buffers);
+        addCases(ByteBuffer.allocate(SIZE*2).order(ByteOrder.LITTLE_ENDIAN).asCharBuffer(),
+                 buffers);
+
+        // direct
+        addCases(ByteBuffer.allocateDirect(SIZE*2).order(ByteOrder.BIG_ENDIAN).asCharBuffer(),
+                 buffers);
+        addCases(ByteBuffer.allocateDirect(SIZE*2).order(ByteOrder.LITTLE_ENDIAN).asCharBuffer(),
+                 buffers);
+
+        // read-only buffer backed by a CharSequence
+        buffers.add(CharBuffer.wrap(randomize(CharBuffer.allocate(SIZE))));
+
+        Object[][] params = new Object[buffers.size()][];
+        for (int i = 0; i < buffers.size(); i++) {
+            CharBuffer cb = buffers.get(i);
+            params[i] = new Object[] { cb.getClass().getName(), cb };
+        }
+
+        return params;
+    }
+
+    @Test(dataProvider = "charbuffers")
+    public void testChars(String type, CharBuffer cb) {
+        System.out.format("%s position=%d, limit=%d%n", type, cb.position(), cb.limit());
+        int expected = intSum(cb);
+        assertEquals(cb.chars().sum(), expected);
+        assertEquals(cb.chars().parallel().sum(), expected);
+    }
+}