1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
|
/*
* Copyright 2015 Open Networking Laboratory
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.onlab.util;
import java.util.Timer;
import java.util.concurrent.ExecutorService;
import static com.google.common.base.Preconditions.checkArgument;
import static java.util.concurrent.Executors.newFixedThreadPool;
import static java.util.concurrent.Executors.newSingleThreadExecutor;
import static org.onlab.util.Tools.groupedThreads;
/**
* Utility for managing a set of shared execution resources, such as a timer,
* single thread executor and thread pool executor for use by various parts of
* the platform or by applications.
* <p>
* Whenever possible, use of these shared resources is encouraged over creating
* separate ones.
* </p>
*/
public final class SharedExecutors {
public static final int DEFAULT_POOL_SIZE = 30;
private static SharedExecutorService singleThreadExecutor =
new SharedExecutorService(
newSingleThreadExecutor(groupedThreads("onos/shared",
"onos-single-executor")));
private static SharedExecutorService poolThreadExecutor =
new SharedExecutorService(
newFixedThreadPool(DEFAULT_POOL_SIZE,
groupedThreads("onos/shared",
"onos-pool-executor-%d")));
private static SharedTimer sharedTimer = new SharedTimer();
// Ban public construction
private SharedExecutors() {
}
/**
* Returns the shared single thread executor.
*
* @return shared single thread executor
*/
public static ExecutorService getSingleThreadExecutor() {
return singleThreadExecutor;
}
/**
* Returns the shared thread pool executor.
*
* @return shared executor pool
*/
public static ExecutorService getPoolThreadExecutor() {
return poolThreadExecutor;
}
/**
* Returns the shared timer.
*
* @return shared timer
*/
public static Timer getTimer() {
return sharedTimer;
}
/**
* Sets the shared thread pool size.
*
* @param poolSize new pool size
*/
public static void setPoolSize(int poolSize) {
checkArgument(poolSize > 0, "Shared pool size size must be greater than 0");
poolThreadExecutor.setBackingExecutor(
newFixedThreadPool(poolSize, groupedThreads("onos/shared",
"onos-pool-executor-%d")));
}
/**
* Shuts down all shared timers and executors and therefore should be
* called only by the framework.
*/
public static void shutdown() {
sharedTimer.shutdown();
singleThreadExecutor.backingExecutor().shutdown();
poolThreadExecutor.backingExecutor().shutdown();
}
// Timer extension which does not allow outside cancel method.
private static class SharedTimer extends Timer {
public SharedTimer() {
super("onos-shared-timer");
}
@Override
public void cancel() {
throw new UnsupportedOperationException("Cancel of shared timer is not allowed");
}
private void shutdown() {
super.cancel();
}
}
}
|
