1 /*
   2  * Copyright (c) 2014 Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package org.openjdk.bench.java.lang;
  24 
  25 import org.openjdk.jmh.annotations.Benchmark;
  26 import org.openjdk.jmh.annotations.BenchmarkMode;
  27 import org.openjdk.jmh.annotations.Mode;
  28 import org.openjdk.jmh.annotations.OutputTimeUnit;
  29 import org.openjdk.jmh.annotations.Scope;
  30 import org.openjdk.jmh.annotations.Setup;
  31 import org.openjdk.jmh.annotations.State;
  32 import org.openjdk.jmh.infra.Blackhole;
  33 
  34 import java.util.concurrent.TimeUnit;
  35 
  36 /**
  37  * Tests java.lang.Class.forName() with various inputs.
  38  */
  39 @BenchmarkMode(Mode.AverageTime)
  40 @OutputTimeUnit(TimeUnit.NANOSECONDS)
  41 @State(Scope.Thread)
  42 public class ClassForName {
  43 
  44     private String aName, bName, cName;
  45 
  46     @Setup
  47     public void setup() {
  48         aName = A.class.getName();
  49         bName = B.class.getName();
  50         cName = C.class.getName();
  51     }
  52 
  53     /** Calls Class.forName with the same name over and over again. The class asked for exists. */
  54     @Benchmark
  55     public void test1(Blackhole bh) throws ClassNotFoundException {
  56         bh.consume(Class.forName(aName));
  57     }
  58 
  59     /** Calls Class.forName with the three different names over and over again. All classes asked for exist. */
  60     @Benchmark
  61     public void test3(Blackhole bh) throws ClassNotFoundException {
  62         bh.consume(Class.forName(aName));
  63         bh.consume(Class.forName(bName));
  64         bh.consume(Class.forName(cName));
  65     }
  66 
  67     static class A {}
  68     static class B {}
  69     static class C {}
  70 }