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1
8
9 package foxtrot.pumps;
10
11 import java.awt.AWTEvent  ;
12 import java.awt.ActiveEvent ;
13 import java.awt.Component ;
14 import java.awt.EventQueue ;
15 import java.awt.MenuComponent ;
16 import java.awt.Toolkit ;
17 import java.lang.reflect.Method ;
18 import java.security.AccessController ;
19 import java.security.PrivilegedAction ;
20
21 import foxtrot.EventPump;
22 import foxtrot.Task;
23
24
29 public class QueueEventPump implements EventPump, EventFilterable
30 {
31 private static final boolean debug = false;
32
33 private EventFilter filter;
34
35 public void setEventFilter(EventFilter filter)
36 {
37 this.filter = filter;
38 }
39
40 public EventFilter getEventFilter()
41 {
42 return filter;
43 }
44
45 public void pumpEvents(Task task)
46 {
47 if (task == null) return;
48
49 EventQueue queue = getEventQueue();
50
51 if (debug) System.out.println("[QueueEventPump] Start pumping events - Pump is " + this + " - Task is " + task);
52
53 while (!task.isCompleted())
54 {
55 try
56 {
57 AWTEvent event = queue.getNextEvent();
58
59 if (debug) System.out.println("[QueueEventPump] Next Event: " + event);
60
61 if (filter != null && !filter.accept(event))
62 {
63 if (debug) System.out.println("[QueueEventPump] Filtered out AWT Event: " + event + " by filter " + filter);
64 continue;
65 }
66
67 try
68 {
69 dispatchEvent(queue, event);
70 }
71 catch (Throwable x)
72 {
73 handleThrowable(x);
74 }
75 }
76 catch (InterruptedException x)
77 {
78 Thread.currentThread().interrupt();
80 break;
81 }
82 }
83
84 if (debug) System.out.println("[QueueEventPump] Stop pumping events - Pump is " + this + " - Task is " + task);
85 }
86
87
92 private void dispatchEvent(EventQueue queue, AWTEvent event)
93 {
94 Object source = event.getSource();
95
96 if (event instanceof ActiveEvent )
97 ((ActiveEvent )event).dispatch();
98 else if (source instanceof Component )
99 ((Component )source).dispatchEvent(event);
100 else if (source instanceof MenuComponent )
101 ((MenuComponent )source).dispatchEvent(event);
102 else
103 System.err.println("[QueueEventPump] Unable to dispatch event " + event);
104 }
105
106
111 private void handleThrowable(Throwable x)
112 {
113 String handlerName = (String )AccessController.doPrivileged(new PrivilegedAction ()
114 {
115 public Object run()
116 {
117 return System.getProperty("sun.awt.exception.handler");
118 }
119 });
120
121 if (handlerName != null)
122 {
123 try
124 {
125 Object handler = Thread.currentThread().getContextClassLoader().loadClass(handlerName).newInstance();
126 Method handle = handler.getClass().getMethod("handle", new Class []{Throwable .class});
127 handle.invoke(handler, new Object []{x});
128 return;
129 }
130 catch (Throwable ignored)
131 {
132 System.err.println("[QueueEventPump] Exception occurred while invoking AWT exception handler: " + ignored);
133 }
135 }
136
137 System.err.println("[QueueEventPump] Exception occurred during event dispatching:");
138 x.printStackTrace();
139 }
140
141 private EventQueue getEventQueue()
142 {
143 return (EventQueue )AccessController.doPrivileged(new PrivilegedAction ()
144 {
145 public Object run()
146 {
147 return Toolkit.getDefaultToolkit().getSystemEventQueue();
148 }
149 });
150 }
151 }
152 |
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