OpenJDK / jdk / jdk
changeset 53901:0448cb38c418
8011135: (bf) CharBuffer.put(String) is slow because of String.charAt() call for each char
Reviewed-by: alanb, redestad
author | bpb |
---|---|
date | Fri, 22 Feb 2019 10:13:33 -0800 |
parents | 4008a1d5cfbc |
children | 7a6fd71449e7 |
files | src/java.base/share/classes/java/nio/Heap-X-Buffer.java.template test/micro/org/openjdk/bench/java/nio/CharBuffers.java |
diffstat | 2 files changed, 85 insertions(+), 0 deletions(-) [+] |
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--- a/src/java.base/share/classes/java/nio/Heap-X-Buffer.java.template Fri Feb 22 09:47:00 2019 -0800 +++ b/src/java.base/share/classes/java/nio/Heap-X-Buffer.java.template Fri Feb 22 10:13:33 2019 -0800 @@ -270,6 +270,25 @@ #end[rw] } +#if[char] + + public $Type$Buffer put(String src, int start, int end) { + int length = end - start; + checkBounds(start, length, src.length()); + if (isReadOnly()) + throw new ReadOnlyBufferException(); + int pos = position(); + int lim = limit(); + int rem = (pos <= lim) ? lim - pos : 0; + if (length > rem) + throw new BufferOverflowException(); + src.getChars(start, end, hb, ix(pos)); + position(pos + length); + return this; + } + +#end[char] + public $Type$Buffer compact() { #if[rw] System.arraycopy(hb, ix(position()), hb, ix(0), remaining());
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/test/micro/org/openjdk/bench/java/nio/CharBuffers.java Fri Feb 22 10:13:33 2019 -0800 @@ -0,0 +1,66 @@ +/* + * Copyright (c) 2019, 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 org.openjdk.bench.java.nio; + +import java.nio.CharBuffer; +import java.util.Arrays; +import java.util.concurrent.TimeUnit; + +import org.openjdk.jmh.annotations.Benchmark; +import org.openjdk.jmh.annotations.BenchmarkMode; +import org.openjdk.jmh.annotations.Level; +import org.openjdk.jmh.annotations.Mode; +import org.openjdk.jmh.annotations.OutputTimeUnit; +import org.openjdk.jmh.annotations.Param; +import org.openjdk.jmh.annotations.Scope; +import org.openjdk.jmh.annotations.Setup; +import org.openjdk.jmh.annotations.State; + +@BenchmarkMode(Mode.AverageTime) +@OutputTimeUnit(TimeUnit.NANOSECONDS) +@State(Scope.Thread) +public class CharBuffers { + + @Param({"2", "256", "16384"}) + public int numChars; + + public String str; + public CharBuffer buf; + + @Setup(Level.Iteration) + public void createString() { + char[] c = new char[numChars]; + Arrays.fill(c, 'X'); + str = String.valueOf(c); + buf = CharBuffer.allocate(numChars); + } + + @Benchmark + public CharBuffer putString() { + buf.clear(); + return buf.put(str); + } + +}