1/*
2 * Copyright (c) 2016, 2017, 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/*
25 * @test
26 * @bug 8165246
27 * @summary Test has_previous_versions flag and processing during class unloading.
28 * @library /test/lib
29 * @modules java.base/jdk.internal.misc
30 * @modules java.compiler
31 *          java.instrument
32 *          jdk.jartool/sun.tools.jar
33 * @run main RedefineClassHelper
34 * @run main/othervm RedefinePreviousVersions test
35 */
36
37import jdk.test.lib.process.ProcessTools;
38import jdk.test.lib.process.OutputAnalyzer;
39
40public class RedefinePreviousVersions {
41
42    public static String newB =
43                "class RedefinePreviousVersions$B {" +
44                "}";
45
46    static class B { }
47
48    public static String newRunning =
49        "class RedefinePreviousVersions$Running {" +
50        "    public static volatile boolean stop = true;" +
51        "    public static volatile boolean running = true;" +
52        "    static void localSleep() { }" +
53        "    public static void infinite() { }" +
54        "}";
55
56    static class Running {
57        public static volatile boolean stop = false;
58        public static volatile boolean running = false;
59        static void localSleep() {
60          try{
61            Thread.sleep(10); // sleep for 10 ms
62          } catch(InterruptedException ie) {
63          }
64        }
65
66        public static void infinite() {
67            running = true;
68            while (!stop) { localSleep(); }
69        }
70    }
71
72    public static void main(String[] args) throws Exception {
73
74        if (args.length > 0) {
75
76            // java -javaagent:redefineagent.jar -Xlog:stuff RedefinePreviousVersions
77            ProcessBuilder pb = ProcessTools.createJavaProcessBuilder( "-javaagent:redefineagent.jar",
78               "-Xlog:redefine+class+iklass+add=trace,redefine+class+iklass+purge=trace",
79               "RedefinePreviousVersions");
80            new OutputAnalyzer(pb.start())
81              .shouldContain("Class unloading: has_previous_versions = false")
82              .shouldContain("Class unloading: has_previous_versions = true")
83              .shouldHaveExitValue(0);
84            return;
85        }
86
87        // Redefine a class and create some garbage
88        // Since there are no methods running, the previous version is never added to the
89        // previous_version_list and the flag _has_previous_versions should stay false
90        RedefineClassHelper.redefineClass(B.class, newB);
91
92        for (int i = 0; i < 10 ; i++) {
93            String s = new String("some garbage");
94            System.gc();
95        }
96
97        // Start a class that has a method running
98        new Thread() {
99            public void run() {
100                Running.infinite();
101            }
102        }.start();
103
104        while (!Running.running) {
105            Thread.sleep(10); // sleep for 10 ms
106        }
107
108        // Since a method of newRunning is running, this class should be added to the previous_version_list
109        // of Running, and _has_previous_versions should return true at class unloading.
110        RedefineClassHelper.redefineClass(Running.class, newRunning);
111
112        for (int i = 0; i < 10 ; i++) {
113            String s = new String("some garbage");
114            System.gc();
115        }
116
117        // purge should clean everything up, except Xcomp it might not.
118        Running.stop = true;
119
120        for (int i = 0; i < 10 ; i++) {
121            String s = new String("some garbage");
122            System.gc();
123        }
124    }
125}
126