/* * Copyright (c) 2014 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.lang; import org.openjdk.jmh.annotations.Benchmark; import org.openjdk.jmh.annotations.BenchmarkMode; import org.openjdk.jmh.annotations.Mode; import org.openjdk.jmh.annotations.OutputTimeUnit; import org.openjdk.jmh.annotations.Scope; import org.openjdk.jmh.annotations.Setup; import org.openjdk.jmh.annotations.State; import java.util.concurrent.TimeUnit; /** * Performance test of String.hashCode() function */ @BenchmarkMode(Mode.AverageTime) @OutputTimeUnit(TimeUnit.NANOSECONDS) @State(Scope.Thread) public class StringHashCode { private String hashcode; private String hashcode0; @Setup public void setup() { hashcode = "abcdefghijkl"; hashcode0 = new String(new char[]{72, 90, 100, 89, 105, 2, 72, 90, 100, 89, 105, 2}); } /** * Benchmark testing String.hashCode() with a regular 12 char string with * the result possibly cached in String */ @Benchmark public int cached() { return hashcode.hashCode(); } /** * Benchmark testing String.hashCode() with a 12 char string with the * hashcode = 0 forcing the value to always be recalculated. */ @Benchmark public int notCached() { return hashcode0.hashCode(); } }