testthreadgroup.java

一个网络应用程序主要功能是能够和一人和多人聊天

public class TestThreadGroup
{
	public static void main(String[] args)
	{
		//(1)显示系统线程组的信息
		ThreadGroup systemGroup=Thread.currentThread().getThreadGroup();
		System.out.println("(1)显示系统线程组的信息 : ");
		systemGroup.list();
		
		//（2）将系统线程组的最大优先级减一
		//并且将系统主线程的优先级加一
		systemGroup.setMaxPriority(Thread.MAX_PRIORITY);
		Thread currentThread=Thread.currentThread();
		currentThread.setPriority(currentThread.getPriority()+1);
		System.out.println("（2）将系统线程组的最大优先级减一,"+"并且将系统主线程的优先级加一");
		systemGroup.list();
		
		//（3）创建一个线程组ThreadGroup1，并且将优先级设置最大
	    //在其中创建一个线程，也将其优先级设置为最大
		ThreadGroup threadGroup1=new ThreadGroup("ThreadGroup1");
		threadGroup1.setMaxPriority(Thread.MAX_PRIORITY);
		Thread thread1=new Thread(threadGroup1,"Thread A");
		thread1.setPriority(Thread.MAX_PRIORITY);
		System.out.println("（3）创建一个线程组ThreadGroup1，并且将优先级设置最大(10),");
		System.out.println("在其中创建一个线程Thread A，也将其优先级设置为最大");
		threadGroup1.list();
		
		//（4）将线程组ThreadGroup1的最大优先级减一，然后再将其设为最大
		threadGroup1.setMaxPriority(Thread.MAX_PRIORITY-1);
		threadGroup1.setMaxPriority(Thread.MAX_PRIORITY);
		System.out.println("（4）将线程组ThreadGroup1的最大优先级减一，然后再将其设为最大(10)");
		threadGroup1.list();
		
		//（5）在线程组ThreadGroup1中新建一个线程Thread B，将其优先级设置为最大
		thread1=new Thread(threadGroup1,"Thread B");
		thread1.setPriority(Thread.MAX_PRIORITY );
		System.out.println("（5）在线程组ThreadGroup1中新建一个线程Thread B，"+
						   "将其优先级设置为最大(10)");
		threadGroup1.list();
		
		//（6）将线程组ThreadGroup1的优先级设置为低于线程的默认优先级
		//并且在其中创建一个新的线程Thread C
		threadGroup1.setMaxPriority(Thread.MIN_PRIORITY+2);
		Thread thread2=new Thread(threadGroup1,"Thread C");
		System.out.println("（6）将线程组ThreadGroup1的优先级设置为低于线程的默认优先级");
		System.out.println("   并且在其中创建一个新的线程Thread C : ");
		threadGroup1.list();
		
		//（7）将线程Thread B和Thread C的优先级各减一
		thread1.setPriority(thread1.getPriority()-1);
		thread2.setPriority(thread2.getPriority()-1);
		System.out.println("（7）将线程Thread B和Thread C的优先级各减一: ");
		threadGroup1.list();
		
		//（8）在线程组Thread Group1下创建一个子线程组ThreadGroup2
		ThreadGroup threadGroup2=new ThreadGroup(threadGroup1,"ThreadGroup2");
		System.out.println("（8）在线程组Thread Group1下创建一个子线程组ThreadGroup2: ");
		threadGroup2.list();
		
		//（9）将线程组ThreadGroup2的最大优先级设置为最大
		threadGroup2.setMaxPriority(Thread.MAX_PRIORITY );
		System.out.println("（9）将线程组ThreadGroup2的最大优先级设置为最大(10): ");
		threadGroup2.list();
		
		//（10）在线程组ThreadGroup2下创建线程Thread D和Thread E
		thread1=new Thread(threadGroup2,"Thread D");
		thread1=new Thread(threadGroup2,"Thread E");
		System.out.println("（10）在线程组ThreadGroup2下创建线程Thread D和Thread E.");
		System.out.println("  打印出系统线程组的信息：  ");
		systemGroup.list();
	}
}