1 /*
   2  * Copyright (c) 2017, 2018, Red Hat, Inc. All rights reserved.
   3  *
   4  * This code is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This code is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * version 2 for more details (a copy is included in the LICENSE file that
  12  * accompanied this code).
  13  *
  14  * You should have received a copy of the GNU General Public License version
  15  * 2 along with this work; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  19  * or visit www.oracle.com if you need additional information or have any
  20  * questions.
  21  *
  22  */
  23 
  24 /**
  25  * @test TestHeapDump
  26  * @summary Tests JVMTI heap dumps
  27  * @compile TestHeapDump.java
  28  * @run main/othervm/native/timeout=300 -agentlib:TestHeapDump -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx128m -XX:ShenandoahGCHeuristics=aggressive -XX:+UseCompressedOops TestHeapDump
  29  * @run main/othervm/native/timeout=300 -agentlib:TestHeapDump -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx128m -XX:ShenandoahGCHeuristics=aggressive -XX:-UseCompressedOops TestHeapDump
  30  */
  31 
  32 public class TestHeapDump {
  33 
  34     private static final int NUM_ITER = 10000;
  35 
  36     private static final int ARRAY_SIZE = 1000;
  37 
  38     private static final int EXPECTED_OBJECTS =
  39         ARRAY_SIZE +   // array reachable from instance field
  40         1 +            // static field root
  41         1;             // local field root
  42 
  43     static {
  44         try {
  45             System.loadLibrary("TestHeapDump");
  46         } catch (UnsatisfiedLinkError ule) {
  47             System.err.println("Could not load TestHeapDump library");
  48             System.err.println("java.library.path: "
  49                 + System.getProperty("java.library.path"));
  50             throw ule;
  51         }
  52     }
  53 
  54     native static int heapdump(Class<?> filterClass);
  55 
  56     public static void main(String args[]) {
  57       new TestHeapDump().run();
  58     }
  59 
  60     // This root needs to be discovered
  61     static Object root = new TestObject();
  62 
  63     // This field needs to be discovered
  64     TestObject[] array;
  65 
  66     public void run() {
  67         array = new TestObject[ARRAY_SIZE];
  68         for (int i = 0; i < ARRAY_SIZE; i++) {
  69             array[i] = new TestObject();
  70         }
  71         TestObject localRoot = new TestObject();
  72         for (int i = 0; i < NUM_ITER; i++) {
  73             int numObjs = heapdump(TestObject.class);
  74             if (numObjs != EXPECTED_OBJECTS) {
  75                 throw new RuntimeException("Expected " + EXPECTED_OBJECTS + " objects, but got " + numObjs);
  76             }
  77         }
  78     }
  79 
  80     // We look for the instances of this class during the heap scan
  81     public static class TestObject {}
  82 }