1/*
2 * Copyright (c) 2014, 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 8054823
27 * @summary Tests the setFlag and printFlag attach command
28 * @library /test/lib
29 * @modules java.base/jdk.internal.misc
30 *          java.compiler
31 *          java.management
32 *          jdk.attach/sun.tools.attach
33 *          jdk.internal.jvmstat/sun.jvmstat.monitor
34 * @run main AttachSetGetFlag
35 */
36
37import java.io.BufferedReader;
38import java.io.InputStreamReader;
39import java.io.InputStream;
40import java.lang.reflect.Field;
41import java.nio.file.Files;
42import java.nio.file.Path;
43import java.nio.file.Paths;
44
45import sun.tools.attach.HotSpotVirtualMachine;
46
47import jdk.test.lib.Asserts;
48import jdk.test.lib.Platform;
49import jdk.test.lib.process.ProcessTools;
50import com.sun.tools.attach.VirtualMachine;
51
52public class AttachSetGetFlag {
53
54  public static void main(String... args) throws Exception {
55    // Test a manageable uintx flag.
56    testGetFlag("MaxHeapFreeRatio", "60");
57    testSetFlag("MaxHeapFreeRatio", "50", "60");
58
59    // Test a non-manageable size_t flag.
60    // Since it is not manageable, we can't test the setFlag functionality.
61    testGetFlag("ArrayAllocatorMallocLimit", "128");
62    // testSetFlag("ArrayAllocatorMallocLimit", "64", "128");
63
64    // Test a uint flag.
65    testGetFlag("ParallelGCThreads", "10");
66  }
67
68  public static ProcessBuilder runTarget(String flagName, String flagValue) throws Exception {
69    return ProcessTools.createJavaProcessBuilder(
70        "-XX:+UnlockExperimentalVMOptions",
71        "-XX:" + flagName + "=" + flagValue,
72        "AttachSetGetFlag$Target");
73  }
74
75  public static void testGetFlag(String flagName, String flagValue) throws Exception {
76    ProcessBuilder pb = runTarget(flagName, flagValue);
77
78    Process target = pb.start();
79
80    try {
81      waitForReady(target);
82
83      int pid = (int)target.pid();
84
85      HotSpotVirtualMachine vm = (HotSpotVirtualMachine)VirtualMachine.attach(((Integer)pid).toString());
86
87      // Test Get
88      BufferedReader remoteDataReader = new BufferedReader(new InputStreamReader(
89          vm.printFlag(flagName)));
90
91      boolean foundExpectedLine = false;
92
93      String line = null;
94      while((line = remoteDataReader.readLine()) != null) {
95        System.out.println("printFlag: " + line);
96        if (line.equals("-XX:" + flagName + "=" + flagValue)) {
97          foundExpectedLine = true;
98        }
99      }
100
101      Asserts.assertTrue(foundExpectedLine, "Didn't get the expected output: '-XX:" + flagName + "=" + flagValue + "'");
102
103      vm.detach();
104    }
105    finally {
106      target.destroy();
107      target.waitFor();
108    }
109  }
110
111  public static void testSetFlag(String flagName, String initialFlagValue, String flagValue) throws Exception {
112    ProcessBuilder pb = runTarget(flagName, initialFlagValue);
113
114    Process target = pb.start();
115
116    try {
117      waitForReady(target);
118
119      int pid = (int)target.pid();
120
121      HotSpotVirtualMachine vm = (HotSpotVirtualMachine)VirtualMachine.attach(((Integer)pid).toString());
122
123      // First set the value.
124      BufferedReader remoteDataReader = new BufferedReader(new InputStreamReader(
125          vm.setFlag(flagName, flagValue)));
126
127      String line;
128      while((line = remoteDataReader.readLine()) != null) {
129        System.out.println("setFlag: " + line);
130        // Just empty the stream.
131      }
132      remoteDataReader.close();
133
134      // Then read and make sure we get back the set value.
135      remoteDataReader = new BufferedReader(new InputStreamReader(vm.printFlag(flagName)));
136
137      boolean foundExpectedLine = false;
138      line = null;
139      while((line = remoteDataReader.readLine()) != null) {
140        System.out.println("getFlag: " + line);
141        if (line.equals("-XX:" + flagName + "=" + flagValue)) {
142          foundExpectedLine = true;
143        }
144      }
145
146      Asserts.assertTrue(foundExpectedLine, "Didn't get the expected output: '-XX:" + flagName + "=" + flagValue + "'");
147
148      vm.detach();
149
150    } finally {
151      target.destroy();
152      target.waitFor();
153    }
154  }
155
156  private static void waitForReady(Process target) throws Exception {
157    InputStream os = target.getInputStream();
158    try (BufferedReader reader = new BufferedReader(new InputStreamReader(os))) {
159      String line;
160      while ((line = reader.readLine()) != null) {
161        if ("Ready".equals(line)) {
162          return;
163        }
164      }
165    }
166  }
167
168
169  public static class Target {
170    public static void main(String [] args) throws Exception {
171      System.out.println("Ready");
172      System.out.flush();
173      while (true) {
174        Thread.sleep(1000);
175      }
176    }
177  }
178}
179