1 /*
2 * Copyright (c) 2018, 2019, 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.api.metadata.eventtype;
27
28 import java.io.ByteArrayOutputStream;
29 import java.io.IOException;
30 import java.io.InputStream;
31 import java.nio.file.Files;
32 import java.nio.file.Path;
33
34 import jdk.jfr.Event;
35 import jdk.jfr.EventType;
36 import jdk.jfr.FlightRecorder;
37 import jdk.jfr.Recording;
38 import jdk.jfr.consumer.RecordingFile;
39 import jdk.jfr.internal.JVM;
40
41 /*
42 * @test
43 * @key jfr
44 * @summary Test that verifies event metadata is removed when an event class is unloaded.
45 *
46 * @library /lib/testlibrary
47 * @modules jdk.jfr/jdk.jfr.internal
48 * java.base/jdk.internal.misc
49 *
50 * @run main/othervm jdk.jfr.api.metadata.eventtype.TestUnloadingEventClass
51 */
52 public class TestUnloadingEventClass {
53
54 private static final String EVENT_NAME = "jdk.jfr.api.metadata.eventtype.TestUnloadingEventClass$ToBeUnloaded";
55
56 public static class ToBeUnloaded extends Event {
57 }
58
59 static public class MyClassLoader extends ClassLoader {
60 public MyClassLoader() {
61 super( null);
62 }
63
64 public final Class<?> defineClass(String name, byte[] b) {
65 return super.defineClass(name, b, 0, b.length);
66 }
67 }
68
69 private static final JVM jvm = JVM.getJVM();
70 public static ClassLoader myClassLoader;
71
72 public static void main(String[] args) throws Throwable {
73 assertEventTypeNotAvailable();
74 myClassLoader = createClassLoaderWithEventClass();
75
76 try (Recording r0 = new Recording()) {
77 r0.start();
78 r0.stop();
79 if (getEventType(r0, 0, EVENT_NAME) == null) {
80 throw new Exception("Expected event class to have corresponding event type");
81 }
82 }
83
84 try (Recording r1 = new Recording(); Recording r2 = new Recording(); Recording r3 = new Recording()) {
85 r1.start();
86 r2.start();
87 unLoadEventClass();
88 r3.start();
89
90 assertEventTypeNotAvailable();
91 r3.stop();
92 r2.stop();
93 r1.stop();
94
95 if (getEventType(r1, 1, EVENT_NAME) == null) {
96 throw new Exception("Expected event class to have corresponding event type in recording with all chunks");
97 }
98 if (getEventType(r2, 2, EVENT_NAME) == null) {
99 throw new Exception("Expected event class to have corresponding event type in recording where event class was unloaded");
100 }
101 if (getEventType(r3, 3, EVENT_NAME) != null) {
102 throw new Exception("Unexpected metadata found for event class tha has been unloaded.");
103 }
104 }
105 }
106
107 private static MyClassLoader createClassLoaderWithEventClass() throws Exception {
108 String resourceName = EVENT_NAME.replace('.', '/') + ".class";
109 try (InputStream is = TestUnloadingEventClass.class.getClassLoader().getResourceAsStream(resourceName)) {
110 ByteArrayOutputStream baos = new ByteArrayOutputStream();
111 byte[] buffer = new byte[4096];
112 int byteValue = 0;
113 while ((byteValue = is.read(buffer, 0, buffer.length)) != -1) {
114 baos.write(buffer, 0, byteValue);
115 }
116 baos.flush();
117 MyClassLoader myClassLoader = new MyClassLoader();
118 Class<?> eventClass = myClassLoader.defineClass(EVENT_NAME, baos.toByteArray());
119 if (eventClass == null) {
120 throw new Exception("Could not define test class");
121 }
122 if (eventClass.getSuperclass() != Event.class) {
123 throw new Exception("Superclass should be jdk.jfr.Event");
124 }
125 if (eventClass.getSuperclass().getClassLoader() != null) {
126 throw new Exception("Class loader of jdk.jfr.Event should be null");
127 }
128 if (eventClass.getClassLoader() != myClassLoader) {
129 throw new Exception("Incorrect class loader for event class");
130 }
131 eventClass.newInstance(); // force <clinit>
132 return myClassLoader;
133 }
134 }
135
136 private static void unLoadEventClass() throws Exception {
137 long firstCount = jvm.getUnloadedEventClassCount();
138 System.out.println("Initial unloaded count: " + firstCount);
139 myClassLoader = null;
140 System.out.println("Cleared reference to MyClassLoader");
141 long newCount = 0;
142 do {
143 System.out.println("GC triggered");
144 System.gc();
145 Thread.sleep(1000);
146 newCount = jvm.getUnloadedEventClassCount();
147 System.out.println("Unloaded count: " + newCount);
148 } while (firstCount + 1 != newCount);
149 System.out.println("Event class unloaded!");
150 System.out.println("Event classes currently on the heap:");
151 for (Class<?> eventClass : JVM.getJVM().getAllEventClasses()) {
152 }
153
154 }
155
156 private static void assertEventTypeNotAvailable() throws Exception {
157 for (EventType type : FlightRecorder.getFlightRecorder().getEventTypes()) {
158 if (type.getName().equals(EVENT_NAME)) {
159 throw new Exception("Event type should not be available");
160 }
161 }
162 }
163
164 private static Object getEventType(Recording r, long id, String eventName) throws IOException {
165 Path p = Files.createTempFile("recording-" + id + "_", ".jfr");
166 r.dump(p);
167 try (RecordingFile rf = new RecordingFile(p)) {
168 for (EventType et : rf.readEventTypes()) {
169 if (et.getName().equals(eventName)) {
170 return et;
171 }
172 }
173
174 }
175 return null;
176 }
177 }
178