1 /*
   2  * Copyright (c) 2018, 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 
  26 package jdk.jfr.event.oldobject;
  27 
  28 import java.lang.reflect.Modifier;
  29 import java.util.HashSet;
  30 import java.util.List;
  31 import java.util.Set;
  32 
  33 import jdk.jfr.Recording;
  34 import jdk.jfr.consumer.RecordedEvent;
  35 import jdk.jfr.consumer.RecordedObject;
  36 import jdk.jfr.internal.test.WhiteBox;
  37 import jdk.test.lib.Asserts;
  38 import jdk.test.lib.jfr.EventNames;
  39 import jdk.test.lib.jfr.Events;
  40 
  41 /*
  42  * @test
  43  * @key jfr
  44  * @requires vm.gc == "null"
  45  * @library /test/lib /test/jdk
  46  * @modules jdk.jfr/jdk.jfr.internal.test
  47  * @run main/othervm -XX:TLABSize=2k -Xlog:gc+tlab=trace jdk.jfr.event.oldobject.TestFieldInformation
  48  */
  49 public class TestFieldInformation {
  50 
  51     public static final Object[] testField = new Object[50];
  52 
  53     public static void main(String[] args) throws Exception {
  54         WhiteBox.setWriteAllObjectSamples(true);
  55 
  56         try (Recording recording = new Recording()) {
  57             recording.enable(EventNames.OldObjectSample).withoutStackTrace().with("cutoff", "infinity");
  58             recording.start();
  59 
  60             addToTestField();
  61 
  62             recording.stop();
  63 
  64             List<RecordedEvent> events = Events.fromRecording(recording);
  65             Events.hasEvents(events);
  66             for (RecordedEvent e : events) {
  67                 if (hasValidField(e)) {
  68                     return;
  69                 }
  70             }
  71             System.out.println(events);
  72             Asserts.fail("Could not find old object with field 'testField'");
  73         }
  74     }
  75 
  76     private static boolean hasValidField(RecordedEvent e) throws Exception {
  77         RecordedObject object = e.getValue("object");
  78         Set<Long> visited = new HashSet<>();
  79         while (object != null) {
  80             Long address = object.getValue("address");
  81             if (visited.contains(address)) {
  82                 return false;
  83             }
  84             visited.add(address);
  85             RecordedObject referrer = object.getValue("referrer");
  86             RecordedObject fieldObject = referrer != null ? referrer.getValue("field") : null;
  87             if (fieldObject != null) {
  88                 String name = fieldObject.getValue("name");
  89                 if (name != null && name.equals("testField")) {
  90                     int modifiers = (short) fieldObject.getValue("modifiers");
  91                     if (!Modifier.isStatic(modifiers)) {
  92                         throw new Exception("Field should be static");
  93                     }
  94                     if (!Modifier.isPublic(modifiers)) {
  95                         throw new Exception("Field should be private");
  96                     }
  97                     if (!Modifier.isFinal(modifiers)) {
  98                         throw new Exception("Field should be final");
  99                     }
 100                     if (Modifier.isTransient(modifiers)) {
 101                         throw new Exception("Field should not be transient");
 102                     }
 103                     if (Modifier.isVolatile(modifiers)) {
 104                         throw new Exception("Field should not be volatile");
 105                     }
 106                     return true;
 107                 }
 108             }
 109             object = referrer != null ? referrer.getValue("object") : null;
 110         }
 111         return false;
 112     }
 113 
 114     private static void addToTestField() {
 115         for (int i = 0; i < testField.length; i++) {
 116             // Allocate array to trigger sampling code path for interpreter / c1
 117             testField[i] = new Object[1_000_000];
 118         }
 119     }
 120 }