1 /************************************************************** 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, 14 * software distributed under the License is distributed on an 15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 * KIND, either express or implied. See the License for the 17 * specific language governing permissions and limitations 18 * under the License. 19 * 20 *************************************************************/ 21 22 23 24 package com.sun.star.comp.beans; 25 26 //--------------------------------------------------------------------------- 27 /** Helper class to watch calls into AOO with a timeout. 28 */ 29 // Do not add the thread instances to a threadgroup. When testing the bean in 30 // an applet it turned out the ThreadGroup was in an inconsistent state 31 // after navigating off the site that contains the applet and back to it. 32 // That was tested with a Sun JRE 1.4.2_06 33 public class CallWatchThread extends Thread 34 { 35 private static boolean DEBUG = false; 36 37 private Thread aWatchedThread; 38 private String aTag; 39 private boolean bAlive; 40 private long nTimeout; 41 CallWatchThread(long nTimeout)42 public CallWatchThread(long nTimeout) 43 { 44 this(nTimeout, ""); 45 } 46 CallWatchThread( long nTimeout, String aTag )47 public CallWatchThread( long nTimeout, String aTag ) 48 { 49 super(aTag); 50 this.aWatchedThread = Thread.currentThread(); 51 this.nTimeout = nTimeout; 52 53 this.aTag = aTag; 54 setDaemon( true ); 55 dbgPrint( "CallWatchThread(" + this + ").start(" + aTag + ")" ); 56 start(); 57 } 58 cancel()59 public void cancel() 60 throws java.lang.InterruptedException 61 { 62 dbgPrint( "CallWatchThread(" + this + ".cancel(" + aTag + ")" ); 63 if ( aWatchedThread != null && aWatchedThread != Thread.currentThread() ) 64 throw new RuntimeException( "wrong thread" ); 65 aWatchedThread = null; 66 if ( interrupted() ) 67 throw new InterruptedException(); 68 } 69 restart()70 public synchronized void restart() 71 throws java.lang.InterruptedException 72 { 73 dbgPrint( "CallWatchThread(" + this + ".restart(" + aTag + ")" ); 74 if ( aWatchedThread != null && aWatchedThread != Thread.currentThread() ) 75 throw new RuntimeException( "wrong thread" ); 76 bAlive = true; 77 if ( interrupted() ) 78 throw new InterruptedException(); 79 notify(); 80 } 81 run()82 public void run() 83 { 84 dbgPrint( "CallWatchThread(" + this + ".run(" + aTag + ") ***** STARTED *****" ); 85 long n = 0; 86 while ( aWatchedThread != null ) 87 { 88 dbgPrint( "CallWatchThread(" + this + ").run(" + aTag + ") running #" + ++n ); 89 synchronized(this) 90 { 91 bAlive = false; 92 try 93 { 94 wait( nTimeout ); 95 } 96 catch ( java.lang.InterruptedException aExc ) 97 { 98 bAlive = false; 99 } 100 101 // watched thread seems to be dead (not answering)? 102 if ( !bAlive && aWatchedThread != null ) 103 { 104 dbgPrint( "CallWatchThread(" + this + ").run(" + aTag + ") interrupting" ); 105 aWatchedThread.interrupt(); 106 aWatchedThread = null; 107 } 108 } 109 } 110 111 dbgPrint( "CallWatchThread(" + this + ").run(" + aTag + ") terminated" ); 112 } 113 dbgPrint( String aMessage )114 private void dbgPrint( String aMessage ) 115 { 116 if (DEBUG) 117 System.err.println( "OOoBean: " + aMessage ); 118 } 119 } 120