-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathThreadPool.java
More file actions
127 lines (110 loc) · 3.67 KB
/
ThreadPool.java
File metadata and controls
127 lines (110 loc) · 3.67 KB
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
124
125
126
127
package com.itcode.javaadv;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
/**
* 线程池类，线程管理器：创建线程，执行任务，销毁线程，获取线程基本信息
*/
public final class ThreadPool {
// 线程池中默认线程的个数为5
private static int worker_num = 5;
// 已处理的任务
private static volatile int finished_task = 0;
// 工作线程
private WorkThread[] workThrads;
// 创建线程池,worker_num为线程池中工作线程的个数
private ThreadPool(int worker_num) {
ThreadPool.worker_num = worker_num;
workThrads = new WorkThread[worker_num];
for (int i = 0; i < worker_num; i++) {
workThrads[i] = new WorkThread(i + "");
workThrads[i].start();// 开启线程池中的线程
}
}
private static ThreadPool threadPool;
// 单例模式，获得一个指定线程个数的线程池,worker_num(>0)为线程池中工作线程的个数
public static ThreadPool getThreadPool(int worker_num1) {
if (worker_num1 <= 0)
worker_num1 = ThreadPool.worker_num;
if (threadPool == null)
threadPool = new ThreadPool(worker_num1);
return threadPool;
}
// 任务队列，作为一个缓冲,List线程不安全
private final List<Task> taskQueue = new LinkedList<>();
// 批量执行任务,其实只是把任务加入任务队列，什么时候执行由线程池管理器决定
public void execute(Task[] task) {
synchronized (taskQueue) {
taskQueue.addAll(Arrays.asList(task));
taskQueue.notify();
}
}
// 销毁线程池,该方法保证在所有任务都完成的情况下才销毁所有线程，否则等待任务完成才销毁
public void destroy() {
while (!taskQueue.isEmpty()) {// 如果还有任务没执行完成，就先睡会吧
try {
Thread.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
// 工作线程停止工作，且置为null
for (int i = 0; i < worker_num; i++) {
workThrads[i].stopWorker();
workThrads[i] = null;
}
threadPool = null;
taskQueue.clear();// 清空任务队列
}
// 返回任务队列的长度，即还没处理的任务个数
public int getWaitTasknumber() {
return taskQueue.size();
}
// 覆盖toString方法，返回线程池信息：工作线程个数和已完成任务个数
@Override
public String toString() {
return "WorkThread number:" + worker_num + " finished task number:" + finished_task + " wait task number:"
+ getWaitTasknumber();
}
/**
* 内部类，工作线程
*/
private class WorkThread extends Thread {
// 该工作线程是否有效，用于结束该工作线程
private boolean isRunning = true;
String name;
public WorkThread(String name) {
this.name = name;
}
@Override
public void run() {
Task r = null;
while (isRunning) {// 注意，若线程无效则自然结束run方法，该线程就没用了
synchronized (taskQueue) {
while (isRunning && taskQueue.isEmpty()) {// 队列为空
try {
taskQueue.wait(20);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
if (!taskQueue.isEmpty())
r = taskQueue.remove(0);// 取出任务
}
if (r != null) {
System.out.println(
name + "＋＋＋＋线程" + Thread.currentThread().getName() + "开始工作,其任务名为:" + r.getName() + "＋＋＋＋");
r.run();// 执行任务
}
System.out.println(
name + "﹣﹣﹣﹣线程" + Thread.currentThread().getName() + "结束工作,其任务名为:" + r.getName() + "﹣﹣﹣﹣");
finished_task++;
r = null;
}
}
// 停止工作，让该线程自然执行完run方法，自然结束
public void stopWorker() {
isRunning = false;
}
}
}