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1
34
35
36 package com.micronova.jsp.tag;
37
38 import java.util.*;
39
40
41
42 public class SynchronizedTag extends YuzuTag
43 {
44 protected static final Map __lock = new HashMap();
45
46 protected boolean _isHoldingLock;
47 protected long _waitTime;
48 protected Object  _lockId;
49
50 protected void init()
51 {
52 super.init();
53
54 _isHoldingLock = false;
55 _waitTime = 0L;
56 _lockId = null;
57 }
58
59 public void setWaitTime(Object expression) throws Exception
60 {
61 _waitTime = ((Long )evaluateAttribute("waitTime", expression, Long .class)).longValue();
62 }
63
64 public void setLockId(Object expression) throws Exception
65 {
66 _lockId = evaluateAttribute("lockId", expression, Object .class);
67 }
68
69 public void doPrepare() throws Exception
70 {
71 Object lockId = _lockId;
72
73 Object lockObject = null;
74
75 Thread currentThread = Thread.currentThread();
76
77 synchronized(__lock)
78 {
79 lockObject = __lock.get(lockId);
80
81 if (lockObject == null)
82 {
83 __lock.put(lockId, (lockId instanceof String ) ? currentThread : lockId);
84 }
85 }
86
87 if (currentThread != lockObject)
88 {
89 if (lockObject != null)
90 {
91 synchronized(lockObject)
92 {
93 lockObject.wait(_waitTime);
94
95 synchronized(__lock)
96 {
97 lockObject = __lock.get(lockId);
98
99 if (lockObject != null)
100 {
101 throw new Exception ("thread lock timeout");
102 }
103 else
104 {
105 __lock.put(lockId, (lockId instanceof String ) ? currentThread: lockId);
106 }
107 }
108 }
109 }
110
111 _isHoldingLock = true;
112 }
113
114 super.doPrepare();
115 }
116
117 public void cleanup()
118 {
119 super.cleanup();
120
121 if (_isHoldingLock)
122 {
123 Object lockId = _lockId;
124
125 try
126 {
127 synchronized(__lock)
128 {
129 Object lockObject = __lock.remove(lockId);
130
131 if (lockObject != null)
132 {
133 synchronized(lockObject)
134 {
135 lockObject.notify();
136 }
137 }
138 }
139 }
140 catch (Exception e)
141 {
142 e.printStackTrace();
143 }
144 }
145 }
146 }
147 |
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