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1
14 package org.aspectj.runtime.internal.cflowstack;
15
16 import java.util.Iterator  ;
17 import java.util.List ;
18 import java.util.ArrayList ;
19 import java.util.Enumeration ;
20 import java.util.Hashtable ;
21
22 public class ThreadCounterImpl11 implements ThreadCounter {
23 private Hashtable counters = new Hashtable ();
24 private Thread cached_thread;
25 private Counter cached_counter;
26
27 private int change_count = 0;
28 private static final int COLLECT_AT = 20000;
29 private static final int MIN_COLLECT_AT = 100;
30
31 static class Counter {
32 protected int value = 0;
33 }
34
35 private synchronized Counter getThreadCounter() {
36 if (Thread.currentThread() != cached_thread) {
37 cached_thread = Thread.currentThread();
38 cached_counter = (Counter)counters.get(cached_thread);
39 if (cached_counter == null) {
40 cached_counter = new Counter();
41 counters.put(cached_thread, cached_counter);
42 }
43 change_count++;
44 int size = Math.max(1, counters.size()); if (change_count > Math.max(MIN_COLLECT_AT, COLLECT_AT/size)) {
47 List dead_stacks = new ArrayList ();
48 for (Enumeration e = counters.keys(); e.hasMoreElements(); ) {
49 Thread t = (Thread )e.nextElement();
50 if (!t.isAlive()) dead_stacks.add(t);
51 }
52 for (Iterator e = dead_stacks.iterator(); e.hasNext(); ) {
53 Thread t = (Thread )e.next();
54 counters.remove(t);
55 }
56 change_count = 0;
57 }
58 }
59 return cached_counter;
60 }
61
62 public void inc() {
63 getThreadCounter().value++;
64 }
65
66 public void dec() {
67 getThreadCounter().value--;
68 }
69
70 public boolean isNotZero() {
71 return getThreadCounter().value!=0;
72 }
73
74 }
75 |
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