1 /*
2 * Copyright 2012 SAP AG. 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 FieldMonitor.java
26 * @bug 7158988
27 * @key regression
28 * @summary verify jvm does not crash while debugging
29 * @run compile TestPostFieldModification.java
30 * @run main/othervm FieldMonitor
31 * @author axel.siebenborn@sap.com
32 */
33 import java.io.BufferedReader;
34 import java.io.IOException;
35 import java.io.InputStream;
36 import java.io.InputStreamReader;
37 import java.util.Iterator;
38 import java.util.List;
39 import java.util.Map;
40
41 import com.sun.jdi.Bootstrap;
42 import com.sun.jdi.Field;
43 import com.sun.jdi.ReferenceType;
44 import com.sun.jdi.VirtualMachine;
45 import com.sun.jdi.connect.Connector;
46 import com.sun.jdi.connect.IllegalConnectorArgumentsException;
47 import com.sun.jdi.connect.LaunchingConnector;
48 import com.sun.jdi.connect.VMStartException;
49 import com.sun.jdi.event.ClassPrepareEvent;
50 import com.sun.jdi.event.Event;
51 import com.sun.jdi.event.EventQueue;
52 import com.sun.jdi.event.EventSet;
53 import com.sun.jdi.event.ModificationWatchpointEvent;
54 import com.sun.jdi.event.VMDeathEvent;
55 import com.sun.jdi.event.VMDisconnectEvent;
56 import com.sun.jdi.request.ClassPrepareRequest;
57 import com.sun.jdi.request.EventRequest;
58 import com.sun.jdi.request.EventRequestManager;
59 import com.sun.jdi.request.ModificationWatchpointRequest;
60
61 public class FieldMonitor {
62
63 public static final String CLASS_NAME = "TestPostFieldModification";
64 public static final String FIELD_NAME = "value";
65 public static final String ARGUMENTS = "-Xshare:off -XX:+PrintGC";
66
67 public static void main(String[] args)
68 throws IOException, InterruptedException {
69
70 //VirtualMachine vm = launchTarget(sb.toString());
71 VirtualMachine vm = launchTarget(CLASS_NAME);
72
73 System.out.println("Vm launched");
74
75 // watch for loaded classes
76 addClassWatch(vm);
77
78 // process events
79 EventQueue eventQueue = vm.eventQueue();
80 // resume the vm
81
82 Process process = vm.process();
83
84
85 // Copy target's output and error to our output and error.
86 Thread outThread = new StreamRedirectThread("out reader", process.getInputStream());
87 Thread errThread = new StreamRedirectThread("error reader", process.getErrorStream());
88
89 errThread.start();
90 outThread.start();
91
92 boolean connected = true;
93 while (connected) {
94 EventSet eventSet = eventQueue.remove();
95 for (Event event : eventSet) {
96 if (event instanceof VMDeathEvent
97 || event instanceof VMDisconnectEvent) {
98 // exit
99 connected = false;
100 } else if (event instanceof ClassPrepareEvent) {
101 // watch field on loaded class
102 System.out.println("ClassPrepareEvent");
103 ClassPrepareEvent classPrepEvent = (ClassPrepareEvent) event;
104 ReferenceType refType = classPrepEvent
105 .referenceType();
106 addFieldWatch(vm, refType);
107 } else if (event instanceof ModificationWatchpointEvent) {
108 System.out.println("sleep for 500 ms");
109 Thread.sleep(500);
110 System.out.println("resume...");
111
112 ModificationWatchpointEvent modEvent = (ModificationWatchpointEvent) event;
113 System.out.println("old="
114 + modEvent.valueCurrent());
115 System.out.println("new=" + modEvent.valueToBe());
116 System.out.println();
117 }
118 }
119 eventSet.resume();
120 }
121 // Shutdown begins when event thread terminates
122 try {
123 errThread.join(); // Make sure output is forwarded
124 outThread.join();
125 } catch (InterruptedException exc) {
126 // we don't interrupt
127 }
128 }
129
130 /**
131 * Find a com.sun.jdi.CommandLineLaunch connector
132 */
133 static LaunchingConnector findLaunchingConnector() {
134 List <Connector> connectors = Bootstrap.virtualMachineManager().allConnectors();
135 Iterator <Connector> iter = connectors.iterator();
136 while (iter.hasNext()) {
137 Connector connector = iter.next();
138 if (connector.name().equals("com.sun.jdi.CommandLineLaunch")) {
139 return (LaunchingConnector)connector;
140 }
141 }
142 throw new Error("No launching connector");
143 }
144 /**
145 * Return the launching connector's arguments.
146 */
147 static Map <String,Connector.Argument> connectorArguments(LaunchingConnector connector, String mainArgs) {
148 Map<String,Connector.Argument> arguments = connector.defaultArguments();
149 for (String key : arguments.keySet()) {
150 System.out.println(key);
151 }
152
153 Connector.Argument mainArg = (Connector.Argument)arguments.get("main");
154 if (mainArg == null) {
155 throw new Error("Bad launching connector");
156 }
157 mainArg.setValue(mainArgs);
158
159 Connector.Argument optionsArg = (Connector.Argument)arguments.get("options");
160 if (optionsArg == null) {
161 throw new Error("Bad launching connector");
162 }
163 optionsArg.setValue(ARGUMENTS);
164 return arguments;
165 }
166
167 static VirtualMachine launchTarget(String mainArgs) {
168 LaunchingConnector connector = findLaunchingConnector();
169 Map arguments = connectorArguments(connector, mainArgs);
170 try {
171 return (VirtualMachine) connector.launch(arguments);
172 } catch (IOException exc) {
173 throw new Error("Unable to launch target VM: " + exc);
174 } catch (IllegalConnectorArgumentsException exc) {
175 throw new Error("Internal error: " + exc);
176 } catch (VMStartException exc) {
177 throw new Error("Target VM failed to initialize: " +
178 exc.getMessage());
179 }
180 }
181
182
183 private static void addClassWatch(VirtualMachine vm) {
184 EventRequestManager erm = vm.eventRequestManager();
185 ClassPrepareRequest classPrepareRequest = erm
186 .createClassPrepareRequest();
187 classPrepareRequest.addClassFilter(CLASS_NAME);
188 classPrepareRequest.setEnabled(true);
189 }
190
191
192 private static void addFieldWatch(VirtualMachine vm,
193 ReferenceType refType) {
194 EventRequestManager erm = vm.eventRequestManager();
195 Field field = refType.fieldByName(FIELD_NAME);
196 ModificationWatchpointRequest modificationWatchpointRequest = erm
197 .createModificationWatchpointRequest(field);
198 modificationWatchpointRequest.setSuspendPolicy(EventRequest.SUSPEND_EVENT_THREAD);
199 modificationWatchpointRequest.setEnabled(true);
200 }
201 }
202
203 class StreamRedirectThread extends Thread {
204
205 private final BufferedReader in;
206
207 private static final int BUFFER_SIZE = 2048;
208
209 /**
210 * Set up for copy.
211 * @param name Name of the thread
212 * @param in Stream to copy from
213 * @param out Stream to copy to
214 */
215 StreamRedirectThread(String name, InputStream in) {
216 super(name);
217 this.in = new BufferedReader(new InputStreamReader(in));
218 }
219
220 /**
221 * Copy.
222 */
223 public void run() {
224 try {
225 String line;
226 while ((line = in.readLine ()) != null) {
227 System.out.println ("testvm: " + line);
228 }
229 System.out.flush();
230 } catch(IOException exc) {
231 System.err.println("Child I/O Transfer - " + exc);
232 }
233 }
234 }