1 /*
   2  * Copyright (c) 2015, 2016, 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 
  24 import org.testng.annotations.Test;
  25 import org.testng.Assert;
  26 
  27 import java.util.concurrent.TimeUnit;
  28 import java.util.concurrent.locks.Condition;
  29 import java.util.concurrent.locks.ReentrantLock;
  30 
  31 import jdk.test.lib.OutputAnalyzer;
  32 import jdk.test.lib.dcmd.CommandExecutor;
  33 import jdk.test.lib.dcmd.PidJcmdExecutor;
  34 
  35 /*
  36  * @test
  37  * @summary
  38  * @library /testlibrary
  39  * @modules java.base/jdk.internal.misc
  40  * @modules java.xml
  41  *          java.management
  42  * @build jdk.test.lib.*
  43  * @build jdk.test.lib.dcmd.*
  44  * @run testng FinalizerInfoTest
  45  */
  46 public class FinalizerInfoTest {
  47     static ReentrantLock lock = new ReentrantLock();
  48     static volatile int wasInitialized = 0;
  49     static volatile int wasTrapped = 0;
  50     static final String cmd = "GC.finalizer_info";
  51     static final int objectsCount = 1000;
  52 
  53     class MyObject {
  54         public MyObject() {
  55             // Make sure object allocation/deallocation is not optimized out
  56             wasInitialized += 1;
  57         }
  58 
  59         protected void finalize() {
  60             // Trap the object in a finalization queue
  61             wasTrapped += 1;
  62             lock.lock();
  63         }
  64     }
  65 
  66     public void run(CommandExecutor executor) {
  67         try {
  68             lock.lock();
  69             for(int i = 0; i < objectsCount; ++i) {
  70                 new MyObject();
  71             }
  72             System.out.println("Objects initialized: " + objectsCount);
  73             System.gc();
  74 
  75             while(wasTrapped < 1) {
  76                 // Waiting for gc thread.
  77             }
  78 
  79             OutputAnalyzer output = executor.execute(cmd);
  80             output.shouldContain("MyObject");
  81         } finally {
  82             lock.unlock();
  83         }
  84     }
  85 
  86     @Test
  87     public void pid() {
  88         run(new PidJcmdExecutor());
  89     }
  90 }