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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package org.openjdk.bench.java.lang;
  26 
  27 import org.openjdk.jmh.annotations.Benchmark;
  28 import org.openjdk.jmh.annotations.BenchmarkMode;
  29 import org.openjdk.jmh.annotations.Mode;
  30 import org.openjdk.jmh.annotations.OutputTimeUnit;
  31 import org.openjdk.jmh.annotations.Scope;
  32 import org.openjdk.jmh.annotations.Setup;
  33 import org.openjdk.jmh.annotations.State;
  34 import org.openjdk.jmh.infra.Blackhole;
  35 
  36 import java.util.concurrent.TimeUnit;
  37 
  38 /**
  39  * Tests java.lang.Class.forName() with various inputs.
  40  */
  41 @BenchmarkMode(Mode.AverageTime)
  42 @OutputTimeUnit(TimeUnit.NANOSECONDS)
  43 @State(Scope.Thread)
  44 public class ClassForName {
  45 
  46     private String aName, bName, cName;
  47 
  48     @Setup
  49     public void setup() {
  50         aName = A.class.getName();
  51         bName = B.class.getName();
  52         cName = C.class.getName();
  53     }
  54 
  55     /** Calls Class.forName with the same name over and over again. The class asked for exists. */
  56     @Benchmark
  57     public void test1(Blackhole bh) throws ClassNotFoundException {
  58         bh.consume(Class.forName(aName));
  59     }
  60 
  61     /** Calls Class.forName with the three different names over and over again. All classes asked for exist. */
  62     @Benchmark
  63     public void test3(Blackhole bh) throws ClassNotFoundException {
  64         bh.consume(Class.forName(aName));
  65         bh.consume(Class.forName(bName));
  66         bh.consume(Class.forName(cName));
  67     }
  68 
  69     static class A {}
  70     static class B {}
  71     static class C {}
  72 }