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21 
22 
23 
24 package com.sun.star.comp.beans;
25 
26 
27 //---------------------------------------------------------------------------
28 /** Helper class to watch calls into OOo with a timeout.
29  */
30 //Do not add the thread instances to a threadgroup. When testing the bean in
31 //an applet it turned out the the ThreadGroup was in an inconsistent state
32 //after navigating off the site that contains the applet and back to it.
33 //That was tested with a Sun JRE 1.4.2_06
34 public class CallWatchThread extends Thread
35 {
36     private static boolean DEBUG = false;
37 
38     private Thread aWatchedThread;
39     private String aTag;
40     private boolean bAlive;
41     private long nTimeout;
42 
CallWatchThread(long nTimeout)43     public CallWatchThread(long nTimeout)
44     {
45         this(nTimeout, "");
46     }
47 
CallWatchThread( long nTimeout, String aTag )48     public CallWatchThread( long nTimeout, String aTag )
49     {
50         super(aTag);
51         this.aWatchedThread = Thread.currentThread();
52         this.nTimeout = nTimeout;
53 
54         this.aTag = aTag;
55         setDaemon( true );
56         dbgPrint( "CallWatchThread(" + this + ").start(" + aTag + ")" );
57         start();
58     }
59 
cancel()60     public void cancel()
61         throws java.lang.InterruptedException
62     {
63         dbgPrint( "CallWatchThread(" + this + ".cancel(" + aTag + ")" );
64         if ( aWatchedThread != null && aWatchedThread != Thread.currentThread() )
65             throw new RuntimeException( "wrong thread" );
66         aWatchedThread = null;
67         if ( interrupted() )
68             throw new InterruptedException();
69     }
70 
restart()71     public synchronized void restart()
72         throws java.lang.InterruptedException
73     {
74         dbgPrint( "CallWatchThread(" + this + ".restart(" + aTag + ")" );
75         if ( aWatchedThread != null && aWatchedThread != Thread.currentThread() )
76             throw new RuntimeException( "wrong thread" );
77         bAlive = true;
78         if ( interrupted() )
79             throw new InterruptedException();
80         notify();
81     }
82 
run()83     public void run()
84     {
85         dbgPrint( "CallWatchThread(" + this + ".run(" + aTag + ") ***** STARTED *****" );
86         long n = 0;
87         while ( aWatchedThread != null )
88         {
89             dbgPrint( "CallWatchThread(" + this + ").run(" + aTag + ") running #" + ++n );
90             synchronized(this)
91             {
92                 bAlive = false;
93                 try
94                 {
95                     wait( nTimeout );
96                 }
97                 catch ( java.lang.InterruptedException aExc )
98                 {
99                     bAlive = false;
100                 }
101 
102                 // watched thread seems to be dead (not answering)?
103                 if ( !bAlive && aWatchedThread != null )
104                 {
105                     dbgPrint( "CallWatchThread(" + this + ").run(" + aTag + ") interrupting" );
106                     aWatchedThread.interrupt();
107                     aWatchedThread = null;
108                 }
109             }
110         }
111 
112         dbgPrint( "CallWatchThread(" + this + ").run(" + aTag + ") terminated" );
113     }
114 
dbgPrint( String aMessage )115     private void dbgPrint( String aMessage )
116 	{
117         if (DEBUG)
118             System.err.println( "OOoBean: " + aMessage );
119 	}
120 }
121 
122 
123 
124 
125