下面举例总结本节所说明的一些概念。SimpleThreads由两个线程组成，第一个是主线程，主线程使用一个Runnable对象MessageLoop创建一个新的线程，并等待该线程结束。如果MessageLoop线程耗时太长，那么主线程将强制中断该线程。
MessageLoop线程打印出一系列的消息，如果被中断，则打印消息并退出：
1 public class SimpleThreads {
2
3 //Display a message, preceded by the name of the current thread
4
5 static void threadMessage(String message) {
6
7 String threadName = Thread.currentThread().getName();
8
9 System.out.format("%s: %s%n", threadName, message);
10
11 }
12
13 private static class MessageLoop implements Runnable {
14
15 public void run() {
16
17 String importantInfo[] = {
18
19 "Mares eat oats",
20
21 "Does eat oats",
22
23 "Little lambs eat ivy",
24
25 "A kid will eat ivy too"
26
27 };
28
29 try {
30
31 for (int i = 0; i < importantInfo.length; i++) {
32
33 //Pause for 4 seconds
34
35 Thread.sleep(4000);
36
37 //Print a message
38
39 threadMessage(importantInfo[i]);
40
41 }
42
43 } catch (InterruptedException e) {
44
45 threadMessage("I wasn't done!");
46
47 }
48
49 }
50
51 }
52
53 public static void main(String args[]) throws InterruptedException {
54
55 //Delay, in milliseconds before we interrupt MessageLoop
56
57 //thread (default one hour).
58
59 long patience = 1000 * 60 * 60;
60
61 //If command line argument present, gives patience in seconds.
62
63 if (args.length > 0) {
64
65 try {
66
67 patience = Long.parseLong(args[0]) * 1000;
68
69 } catch (NumberFormatException e) {
70
71 System.err.println("Argument must be an integer.");
72
73 System.exit(1);
74
75 }
76
77 }
78
79 threadMessage("Starting MessageLoop thread");
80
81 long startTime = System.currentTimeMillis();
82
83 Thread t = new Thread(new MessageLoop());
84
85 t.start();
86
87 threadMessage("Waiting for MessageLoop thread to finish");
88
89 //loop until MessageLoop thread exits
90
91 while (t.isAlive()) {
92
93 threadMessage("Still waiting...");
94
95 //Wait maximum of 1 second for MessageLoop thread to
96
97 //finish.
98
99 t.join(1000);
100
101 if (((System.currentTimeMillis() - startTime) > patience) &&t.isAlive()) {
102
103 threadMessage("Tired of waiting!");
104
105 t.interrupt();
106
107 //Shouldn't be long now -- wait indefinitely
108
109 t.join();
110
111 }
112
113 }
114
115 threadMessage("Finally!");
116
117 }
118
119 }
120
2
3 //Display a message, preceded by the name of the current thread
4
5 static void threadMessage(String message) {
6
7 String threadName = Thread.currentThread().getName();
8
9 System.out.format("%s: %s%n", threadName, message);
10
11 }
12
13 private static class MessageLoop implements Runnable {
14
15 public void run() {
16
17 String importantInfo[] = {
18
19 "Mares eat oats",
20
21 "Does eat oats",
22
23 "Little lambs eat ivy",
24
25 "A kid will eat ivy too"
26
27 };
28
29 try {
30
31 for (int i = 0; i < importantInfo.length; i++) {
32
33 //Pause for 4 seconds
34
35 Thread.sleep(4000);
36
37 //Print a message
38
39 threadMessage(importantInfo[i]);
40
41 }
42
43 } catch (InterruptedException e) {
44
45 threadMessage("I wasn't done!");
46
47 }
48
49 }
50
51 }
52
53 public static void main(String args[]) throws InterruptedException {
54
55 //Delay, in milliseconds before we interrupt MessageLoop
56
57 //thread (default one hour).
58
59 long patience = 1000 * 60 * 60;
60
61 //If command line argument present, gives patience in seconds.
62
63 if (args.length > 0) {
64
65 try {
66
67 patience = Long.parseLong(args[0]) * 1000;
68
69 } catch (NumberFormatException e) {
70
71 System.err.println("Argument must be an integer.");
72
73 System.exit(1);
74
75 }
76
77 }
78
79 threadMessage("Starting MessageLoop thread");
80
81 long startTime = System.currentTimeMillis();
82
83 Thread t = new Thread(new MessageLoop());
84
85 t.start();
86
87 threadMessage("Waiting for MessageLoop thread to finish");
88
89 //loop until MessageLoop thread exits
90
91 while (t.isAlive()) {
92
93 threadMessage("Still waiting...");
94
95 //Wait maximum of 1 second for MessageLoop thread to
96
97 //finish.
98
99 t.join(1000);
100
101 if (((System.currentTimeMillis() - startTime) > patience) &&t.isAlive()) {
102
103 threadMessage("Tired of waiting!");
104
105 t.interrupt();
106
107 //Shouldn't be long now -- wait indefinitely
108
109 t.join();
110
111 }
112
113 }
114
115 threadMessage("Finally!");
116
117 }
118
119 }
120
