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.VMStartEvent;
56 import com.sun.jdi.event.VMDisconnectEvent;
57 import com.sun.jdi.request.ClassPrepareRequest;
58 import com.sun.jdi.request.EventRequest;
59 import com.sun.jdi.request.EventRequestManager;
60 import com.sun.jdi.request.ModificationWatchpointRequest;
61
62 public class FieldMonitor {
63
64 public static final String CLASS_NAME = "TestPostFieldModification";
65 public static final String FIELD_NAME = "value";
66 public static final String ARGUMENTS = "-Xshare:off -XX:+PrintGC";
67
68 public static void main(String[] args)
69 throws IOException, InterruptedException {
70
71 //VirtualMachine vm = launchTarget(sb.toString());
72 VirtualMachine vm = launchTarget(CLASS_NAME);
73
74 System.out.println("Vm launched");
75
76 // process events
77 EventQueue eventQueue = vm.eventQueue();
78 // resume the vm
79
80 Process process = vm.process();
81
82
83 // Copy target's output and error to our output and error.
84 Thread outThread = new StreamRedirectThread("out reader", process.getInputStream());
85 Thread errThread = new StreamRedirectThread("error reader", process.getErrorStream());
86
87 errThread.start();
88 outThread.start();
89
90 boolean connected = true;
91 int watched = 0;
92 while (connected) {
93 try {
94 EventSet eventSet = eventQueue.remove();
95 for (Event event : eventSet) {
96 System.out.println("FieldMonitor-main receives: "+event);
97 if (event instanceof VMStartEvent) {
98 addClassWatch(vm);
99 } else if (event instanceof VMDeathEvent
100 || event instanceof VMDisconnectEvent) {
101 // exit
102 connected = false;
103 } else if (event instanceof ClassPrepareEvent) {
104 // watch field on loaded class
105 System.out.println("ClassPrepareEvent");
106 ClassPrepareEvent classPrepEvent = (ClassPrepareEvent) event;
107 ReferenceType refType = classPrepEvent
108 .referenceType();
109 addFieldWatch(vm, refType);
110 } else if (event instanceof ModificationWatchpointEvent) {
111 watched++;
112 System.out.println("sleep for 500 ms");
113 Thread.sleep(500);
114
115 ModificationWatchpointEvent modEvent = (ModificationWatchpointEvent) event;
116 System.out.println("old="
117 + modEvent.valueCurrent());
118 System.out.println("new=" + modEvent.valueToBe());
119 }
120 }
121 System.out.println("resume...");
122 eventSet.resume();
123 } catch (com.sun.jdi.VMDisconnectedException exc) {
124 // Guess this means it's not connected anymore,
125 // sometimes this happens and everything else hangs, just return.
126 return;
127 }
128 }
129 // Shutdown begins when event thread terminates
130 try {
131 errThread.join(); // Make sure output is forwarded
132 outThread.join();
133 } catch (InterruptedException exc) {
134 // we don't interrupt
135 }
136
137 if (watched != 11) { // init + 10 modifications in TestPostFieldModification class
138 throw new Error("Expected to receive 11 times ModificationWatchpointEvent, but got "+watched);
139 }
140 }
141
142 /**
143 * Find a com.sun.jdi.CommandLineLaunch connector
144 */
145 static LaunchingConnector findLaunchingConnector() {
146 List <Connector> connectors = Bootstrap.virtualMachineManager().allConnectors();
147 Iterator <Connector> iter = connectors.iterator();
148 while (iter.hasNext()) {
149 Connector connector = iter.next();
150 if (connector.name().equals("com.sun.jdi.CommandLineLaunch")) {
151 return (LaunchingConnector)connector;
152 }
153 }
154 throw new Error("No launching connector");
155 }
156 /**
157 * Return the launching connector's arguments.
158 */
159 static Map <String,Connector.Argument> connectorArguments(LaunchingConnector connector, String mainArgs) {
160 Map<String,Connector.Argument> arguments = connector.defaultArguments();
161 for (String key : arguments.keySet()) {
162 System.out.println(key);
163 }
164
165 Connector.Argument mainArg = (Connector.Argument)arguments.get("main");
166 if (mainArg == null) {
167 throw new Error("Bad launching connector");
168 }
169 mainArg.setValue(mainArgs);
170
171 Connector.Argument optionsArg = (Connector.Argument)arguments.get("options");
172 if (optionsArg == null) {
173 throw new Error("Bad launching connector");
174 }
175 optionsArg.setValue(ARGUMENTS);
176 return arguments;
177 }
178
179 static VirtualMachine launchTarget(String mainArgs) {
180 LaunchingConnector connector = findLaunchingConnector();
181 Map arguments = connectorArguments(connector, mainArgs);
182 try {
183 return (VirtualMachine) connector.launch(arguments);
184 } catch (IOException exc) {
185 throw new Error("Unable to launch target VM: " + exc);
186 } catch (IllegalConnectorArgumentsException exc) {
187 throw new Error("Internal error: " + exc);
188 } catch (VMStartException exc) {
189 throw new Error("Target VM failed to initialize: " +
190 exc.getMessage());
191 }
192 }
193
194
195 private static void addClassWatch(VirtualMachine vm) {
196 EventRequestManager erm = vm.eventRequestManager();
197 ClassPrepareRequest classPrepareRequest = erm
198 .createClassPrepareRequest();
199 classPrepareRequest.addClassFilter(CLASS_NAME);
200 classPrepareRequest.setEnabled(true);
201 }
202
203
204 private static void addFieldWatch(VirtualMachine vm,
205 ReferenceType refType) {
206 EventRequestManager erm = vm.eventRequestManager();
207 Field field = refType.fieldByName(FIELD_NAME);
208 ModificationWatchpointRequest modificationWatchpointRequest = erm
209 .createModificationWatchpointRequest(field);
210 modificationWatchpointRequest.setSuspendPolicy(EventRequest.SUSPEND_EVENT_THREAD);
211 modificationWatchpointRequest.setEnabled(true);
212 }
213 }
214
215 class StreamRedirectThread extends Thread {
216
217 private final BufferedReader in;
218
219 private static final int BUFFER_SIZE = 2048;
220
221 /**
222 * Set up for copy.
223 * @param name Name of the thread
224 * @param in Stream to copy from
225 * @param out Stream to copy to
226 */
227 StreamRedirectThread(String name, InputStream in) {
228 super(name);
229 this.in = new BufferedReader(new InputStreamReader(in));
230 }
231
232 /**
233 * Copy.
234 */
235 public void run() {
236 try {
237 String line;
238 while ((line = in.readLine ()) != null) {
239 System.out.println ("testvm: " + line);
240 }
241 System.out.flush();
242 } catch(IOException exc) {
243 System.err.println("Child I/O Transfer - " + exc);
244 }
245 }
246 }