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1
46 package net.jforum.util.concurrent.executor;
47
48 import net.jforum.util.concurrent.Result;
49 import net.jforum.util.concurrent.Task;
50
51
54 class SimpleResult implements Result
55 {
56 private final Task task;
57 private Exception  exception;
58 private Object result;
59 private boolean ready = false;
60 private final Object lock = new Object ();
61
62 SimpleResult(Task task)
63 {
64 this.task = task;
65 }
66
67 public boolean hasThrown() throws IllegalStateException
68 {
69 synchronized(lock) {
70 if(!ready) {
71 throw new IllegalStateException ("task has not completed");
72 }
73
74 return exception != null;
75 }
76 }
77
78 public Object getResult() throws IllegalStateException
79 {
80 synchronized(lock) {
81 if(!ready) {
82 throw new IllegalStateException ("task has not completed");
83 }
84
85 if(exception != null) {
86 throw new IllegalStateException ("task has thrown an exception");
87 }
88
89 return result;
90 }
91 }
92
93 public Exception getException() throws IllegalStateException
94 {
95 synchronized(lock) {
96 if(!ready) {
97 throw new IllegalStateException ("task has not completed");
98 }
99
100 if(exception == null) {
101 throw new IllegalStateException ("task has not thrown an exception");
102 }
103
104 return exception;
105 }
106 }
107
108 public synchronized void waitResult() throws InterruptedException
109 {
110 if(Thread.interrupted()) {
111 throw new InterruptedException ();
112 }
113
114 synchronized(lock) {
115 if(ready) {
116 return;
117 }
118
119 while(!ready) {
120 lock.wait();
121 }
122 }
123 }
124
125 public synchronized boolean poolResult(long timeout) throws InterruptedException
126 {
127 if(Thread.interrupted()) {
128 throw new InterruptedException ();
129 }
130
131 synchronized(lock) {
132 if(ready) {
133 return true;
134 }
135
136 if(timeout <= 0) {
137 return false;
138 }
139
140 long remaining = timeout;
141 long start = System.currentTimeMillis();
142
143 for(;;) {
144 lock.wait(remaining);
145 if(ready) {
146 return true;
147 }
148
149 remaining = timeout - (System.currentTimeMillis() - start);
150 if(remaining <= 0) {
151 return false;
152 }
153 }
154 }
155 }
156
157 void setException(Exception exception)
158 {
159 synchronized(lock) {
160 if(ready) {
161 throw new IllegalStateException ("task allready completed");
162 }
163
164 this.exception = exception;
165 ready = true;
166 lock.notifyAll();
167 }
168 }
169
170 void setResult(Object result)
171 {
172 synchronized(lock) {
173 if(ready) {
174 throw new IllegalStateException ("task allready completed");
175 }
176
177 this.ready = true;
178 this.result = result;
179 lock.notifyAll();
180 }
181 }
182
183 Task getTask()
184 {
185 return task;
186 }
187
188 } |
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