01: /*_############################################################################
02: _##
03: _## SNMP4J - WorkerPool.java
04: _##
05: _## Copyright (C) 2003-2008 Frank Fock and Jochen Katz (SNMP4J.org)
06: _##
07: _## Licensed under the Apache License, Version 2.0 (the "License");
08: _## you may not use this file except in compliance with the License.
09: _## 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, software
14: _## distributed under the License is distributed on an "AS IS" BASIS,
15: _## WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16: _## See the License for the specific language governing permissions and
17: _## limitations under the License.
18: _##
19: _##########################################################################*/
20:
21: package org.snmp4j.util;
22:
23: /**
24: * The <code>WorkerPool</code> interface models an abstract pool of workers
25: * (threads) which can execute {@link WorkerTask}s concurrently.
26: *
27: * @author Frank Fock
28: * @version 1.9
29: */
30: public interface WorkerPool {
31:
32: /**
33: * Executes a task on behalf of this worker pool. If all threads are currently
34: * busy, this method call blocks until a worker gets idle again which is when
35: * the call returns immediately.
36: * @param task
37: * a <code>Runnable</code> to execute.
38: */
39: void execute(WorkerTask task);
40:
41: /**
42: * Tries to execute a task on behalf of this worker pool. If all threads are
43: * currently busy, this method returns <code>false</code>. Otherwise the task
44: * is executed in background.
45: * @param task
46: * a <code>Runnable</code> to execute.
47: * @return
48: * <code>true</code> if the task is executing.
49: */
50: boolean tryToExecute(WorkerTask task);
51:
52: /**
53: * Stops all threads in this worker pool gracefully. This method will not
54: * return until all threads have been terminated and joined successfully.
55: */
56: void stop();
57:
58: /**
59: * Cancels all threads non-blocking by interrupting them.
60: */
61: void cancel();
62:
63: /**
64: * Checks if all workers of the pool are idle.
65: * @return
66: * <code>true</code> if all workers are idle.
67: */
68: boolean isIdle();
69:
70: }
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