9.多线程学习--线程组

package com.jackson.deng.concurrent.chapter1.nine;

import java.util.Date;
import java.util.Random;
import java.util.concurrent.TimeUnit;

/**
* 线程组
* function desc : 有 10 个随机时间休眠的线程 (例如，模拟搜索)，然后当其中一个完成，就中断其余的
* summary : ThreadGroup 类储存线程对象和其他有关联的 ThreadGroup 对象，所以它可以访问他们的所有信息 (例如，状态) 和全部成员的操作表现 (例如，中断)。
* @author jackson
*
*/
public class ThreadGroupTest {
public class SearchTask implements Runnable {
private Result result;

public SearchTask(Result result) {
this.result = result;
}

@Override
public void run() {
String name = Thread.currentThread().getName();
System.out.println("Thread " + name + " : start");
try {
doTask();
result.setName(name);
} catch (InterruptedException e) {
System.out.println("Thread " + name + " : interrupted");
return;
}
System.out.println("Thread " + name + " : finished");
}

private void doTask() throws InterruptedException {
Random r = new Random(new Date().getTime());
int value = (int) (r.nextDouble() * 100);
System.out.println("Thread " + Thread.currentThread().getName() + " waiting : " + value);
TimeUnit.SECONDS.sleep(value);
}
}

public static void main(String[] args) {
//新建一个线程组searchGroup
ThreadGroup group = new ThreadGroup("searchGroup");
Result result = new Result();

ThreadGroupTest test = new ThreadGroupTest();
SearchTask task = test.new SearchTask(result);
for (int i = 0; i < 5; i++) {
Thread thread = new Thread(group, task);
thread.start();
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
System.out.println("Numnber of thread : " + group.activeCount());
System.out.println("The information about thread : ");
group.list();
Thread[] threads = new Thread[group.activeCount()];
group.enumerate(threads);
for (int i = 0; i < group.activeCount(); i++) {
System.out.println("Thread " + threads[i].getName() + " : " + threads[i].getState());
}
waitFinish(group);
group.interrupt();//用interrupt() 方法中断组里的其他线程。
}

private static void waitFinish(ThreadGroup group) {
while (group.activeCount() > 9) {//只有5个,直接跳出完成任务
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}

class Result {
private String name;

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

}

运行结果:

Thread Thread-0 : start

Thread Thread-0 waiting : 23

Thread Thread-1 : start

Thread Thread-1 waiting : 14

Thread Thread-2 : start

Thread Thread-2 waiting : 41

Thread Thread-3 : start

Thread Thread-3 waiting : 31

Thread Thread-4 : start

Thread Thread-4 waiting : 11

Numnber of thread : 5

The information about thread :

java.lang.ThreadGroup[name=searchGroup,maxpri=10]

Thread[Thread-0,5,searchGroup]

Thread[Thread-1,5,searchGroup]

Thread[Thread-2,5,searchGroup]

Thread[Thread-3,5,searchGroup]

Thread[Thread-4,5,searchGroup]

Thread Thread-0 : TIMED_WAITING

Thread Thread-1 : TIMED_WAITING

Thread Thread-2 : TIMED_WAITING

Thread Thread-3 : TIMED_WAITING

Thread Thread-4 : TIMED_WAITING

Thread Thread-0 : interrupted

Thread Thread-1 : interrupted

Thread Thread-2 : interrupted

Thread Thread-3 : interrupted

Thread Thread-4 : interrupted