81 lines
2.6 KiB
Java
81 lines
2.6 KiB
Java
/*
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* Copyright (c) 2014, 2019, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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package org.openjdk.bench.java.lang;
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import org.openjdk.jmh.annotations.Benchmark;
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import org.openjdk.jmh.annotations.BenchmarkMode;
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import org.openjdk.jmh.annotations.Mode;
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import org.openjdk.jmh.annotations.OutputTimeUnit;
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import org.openjdk.jmh.annotations.Scope;
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import org.openjdk.jmh.annotations.Setup;
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import org.openjdk.jmh.annotations.State;
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import java.util.concurrent.TimeUnit;
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/**
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* Performance test of String.hashCode() function
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*/
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@BenchmarkMode(Mode.AverageTime)
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@OutputTimeUnit(TimeUnit.NANOSECONDS)
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@State(Scope.Thread)
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public class StringHashCode {
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private String hashcode;
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private String hashcode0;
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private String empty;
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@Setup
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public void setup() {
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hashcode = "abcdefghijkl";
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hashcode0 = new String(new char[]{72, 90, 100, 89, 105, 2, 72, 90, 100, 89, 105, 2});
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empty = new String();
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}
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/**
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* Benchmark testing String.hashCode() with a regular 12 char string with
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* the result possibly cached in String
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*/
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@Benchmark
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public int cached() {
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return hashcode.hashCode();
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}
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/**
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* Benchmark testing String.hashCode() with a 12 char string with the
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* hashcode = 0 forcing the value to always be recalculated.
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*/
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@Benchmark
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public int notCached() {
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return hashcode0.hashCode();
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}
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/**
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* Benchmark testing String.hashCode() with the empty string. Since the
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* empty String has hashCode = 0, this value is always recalculated.
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*/
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@Benchmark
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public int empty() {
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return empty.hashCode();
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}
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}
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