8305811: (bf) Improve performance of CharBuffer::append(CharSequence[,int,int])

Reviewed-by: alanb
This commit is contained in:
Brian Burkhalter 2023-04-17 20:17:23 +00:00
parent 525a91e3fa
commit 8858d54342
3 changed files with 205 additions and 1 deletions

View File

@ -1,5 +1,5 @@
/*
* Copyright (c) 2000, 2022, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2000, 2023, 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
@ -278,6 +278,60 @@ class Heap$Type$Buffer$RW$
#if[char]
//
// Use getChars() to load chars directly into the heap buffer array.
// For a String or StringBuffer source this improves performance if
// a proper subsequence is being appended as copying to a new intermediate
// String object is avoided. For a StringBuilder where either a subsequence
// or the full sequence of chars is being appended, copying the chars to
// an intermedite String in StringBuilder::toString is avoided.
//
private $Type$Buffer appendChars(CharSequence csq, int start, int end) {
checkSession();
int length = end - start;
int pos = position();
int lim = limit();
int rem = (pos <= lim) ? lim - pos : 0;
if (length > rem)
throw new BufferOverflowException();
if (csq instanceof String str) {
str.getChars(start, end, hb, ix(pos));
} else if (csq instanceof StringBuilder sb) {
sb.getChars(start, end, hb, ix(pos));
} else if (csq instanceof StringBuffer sb) {
sb.getChars(start, end, hb, ix(pos));
}
position(pos + length);
return this;
}
public $Type$Buffer append(CharSequence csq) {
#if[rw]
if (csq instanceof StringBuilder)
return appendChars(csq, 0, csq.length());
return super.append(csq);
#else[rw]
throw new ReadOnlyBufferException();
#end[rw]
}
public $Type$Buffer append(CharSequence csq, int start, int end) {
#if[rw]
if (csq instanceof String || csq instanceof StringBuffer ||
csq instanceof StringBuilder)
return appendChars(csq, start, end);
return super.append(csq, start, end);
#else[rw]
throw new ReadOnlyBufferException();
#end[rw]
}
public $Type$Buffer put(String src, int start, int end) {
#if[rw]
checkSession();

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@ -2005,6 +2005,8 @@ public abstract sealed class $Type$Buffer
public $Type$Buffer append(CharSequence csq) {
if (csq == null)
return put("null");
else if (csq instanceof CharBuffer cb)
return put(cb);
else
return put(csq.toString());
}
@ -2042,6 +2044,13 @@ public abstract sealed class $Type$Buffer
* @since 1.5
*/
public $Type$Buffer append(CharSequence csq, int start, int end) {
if (csq instanceof CharBuffer cb) {
int pos = position();
int length = end - start;
put(pos, cb, start, length);
position(pos + length);
return this;
}
CharSequence cs = (csq == null ? "null" : csq);
return put(cs.subSequence(start, end).toString());
}

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@ -0,0 +1,141 @@
/*
* Copyright (c) 2023, 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.
*/
package org.openjdk.bench.java.nio;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.util.Arrays;
import java.util.concurrent.TimeUnit;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Warmup;
/**
* Benchmark for {@code CharBuffer} implementations of the {@code Appendable}
* methods which accept a {@code CharSequence} source.
*/
@Warmup(iterations = 5, time = 500, timeUnit = TimeUnit.MILLISECONDS)
@Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
@State(Scope.Benchmark)
@Fork(1)
public class CharBufferAppend {
static final int SIZE = 8192;
static String str;
static StringBuffer strbuf;
static StringBuilder strbld;
static CharBuffer hbDst;
static CharBuffer hbSrc;
static CharBuffer dbSrc;
static CharBuffer dbDst;
static {
char[] chars = new char[SIZE];
Arrays.fill(chars, (char)27);
strbld = new StringBuilder(SIZE);
strbld.append(chars);
str = strbld.toString();
strbuf = new StringBuffer(SIZE);
strbuf.append(chars);
hbDst = CharBuffer.allocate(SIZE);
hbSrc = CharBuffer.wrap(chars);
dbDst = ByteBuffer.allocateDirect(2*SIZE).asCharBuffer();
dbSrc = ByteBuffer.allocateDirect(2*SIZE).asCharBuffer();
dbSrc.put(chars);
dbSrc.clear();
};
@Benchmark
public CharBuffer appendDirectToDirect() {
dbDst.clear();
dbSrc.clear();
return dbDst.append(dbSrc);
}
@Benchmark
public CharBuffer appendDirectToHeap() {
hbDst.clear();
dbSrc.clear();
return hbDst.append(dbSrc);
}
@Benchmark
public CharBuffer appendHeapToHeap() {
hbDst.clear();
hbSrc.clear();
return hbDst.append(hbSrc);
}
@Benchmark
public CharBuffer appendHeapToDirect() {
dbDst.clear();
hbSrc.clear();
return dbDst.append(hbSrc);
}
@Benchmark
public CharBuffer appendString() {
hbDst.clear();
return hbDst.append(str);
}
@Benchmark
public CharBuffer appendStringBuffer() {
hbDst.clear();
return hbDst.append(strbuf);
}
@Benchmark
public CharBuffer appendStringBuilder() {
hbDst.clear();
return hbDst.append(strbld);
}
@Benchmark
public CharBuffer appendSubString() {
hbDst.clear();
return hbDst.append(str, SIZE/4, 3*SIZE/4);
}
@Benchmark
public CharBuffer appendSubStringBuffer() {
hbDst.clear();
return hbDst.append(strbuf, SIZE/4, 3*SIZE/4);
}
@Benchmark
public CharBuffer appendSubStringBuilder() {
hbDst.clear();
return hbDst.append(strbld, SIZE/4, 3*SIZE/4);
}
}