View Javadoc
1   /*
2    * Copyright (c) 1998, 2011, 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  /*
27   * This source code is provided to illustrate the usage of a given feature
28   * or technique and has been deliberately simplified. Additional steps
29   * required for a production-quality application, such as security checks,
30   * input validation and proper error handling, might not be present in
31   * this sample code.
32   */
33  
34  
35  package com.sun.tools.example.debug.bdi;
36  
37  import com.sun.jdi.VirtualMachine;
38  import com.sun.jdi.VMDisconnectedException;
39  
40  /**
41   * Our repository of what we know about the state of one
42   * running VM.
43   */
44  class Session {
45  
46      final VirtualMachine vm;
47      final ExecutionManager runtime;
48      final OutputListener diagnostics;
49  
50      boolean running = true;  // Set false by JDIEventSource
51      boolean interrupted = false;  // Set false by JDIEventSource
52  
53      private JDIEventSource eventSourceThread = null;
54      private int traceFlags;
55      private boolean dead = false;
56  
57      public Session(VirtualMachine vm, ExecutionManager runtime,
58                     OutputListener diagnostics) {
59          this.vm = vm;
60          this.runtime = runtime;
61          this.diagnostics = diagnostics;
62          this.traceFlags = VirtualMachine.TRACE_NONE;
63      }
64  
65      /**
66       * Determine if VM is interrupted, i.e, present and not running.
67       */
68      public boolean isInterrupted() {
69          return interrupted;
70      }
71  
72      public void setTraceMode(int traceFlags) {
73          this.traceFlags = traceFlags;
74          if (!dead) {
75              vm.setDebugTraceMode(traceFlags);
76          }
77      }
78  
79      public boolean attach() {
80          vm.setDebugTraceMode(traceFlags);
81          diagnostics.putString("Connected to VM");
82          eventSourceThread = new JDIEventSource(this);
83          eventSourceThread.start();
84          return true;
85      }
86  
87      public void detach() {
88          if (!dead) {
89              eventSourceThread.interrupt();
90              eventSourceThread = null;
91              //### The VM may already be disconnected
92              //### if the debuggee did a System.exit().
93              //### Exception handler here is a kludge,
94              //### Rather, there are many other places
95              //### where we need to handle this exception,
96              //### and initiate a detach due to an error
97              //### condition, e.g., connection failure.
98              try {
99                  vm.dispose();
100             } catch (VMDisconnectedException ee) {}
101             dead = true;
102             diagnostics.putString("Disconnected from VM");
103         }
104     }
105 }