java多线程简单的小例子

java有两种方式实现多线程，一种是继承Thread类，一种实现Runnable接口。

package com.hgf.thread;

public class ExtThread extends Thread {
	private String name;

	public ExtThread(String name) {
		this.name = name;
	}

	public void run() {
		for (int i = 0; i < 10; i++) {
			System.out.println("线程开始：" + name + ",i=" + i);
		}
	}

	public static void main(String[] args) {
		ExtThread mt1 = new ExtThread("线程a");
		ExtThread mt2 = new ExtThread("线程b");
		//run 会先执行完线程a在执行线程b
		mt1.run();
		mt2.run();
	}
}

package com.hgf.thread;

public class ExtThread extends Thread {
	private String name;

	public ExtThread(String name) {
		this.name = name;
	}

	public void run() {
		for (int i = 0; i < 10; i++) {
			System.out.println("线程开始：" + name + ",i=" + i);
		}
	}

	public static void main(String[] args) {
		ExtThread mt1 = new ExtThread("线程a");
		ExtThread mt2 = new ExtThread("线程b");
		//start 会交叉运行
		mt1.start();
		mt2.start();
	}
}

package com.hgf.thread;

public class ImpRunnable implements Runnable {
    private String name;
	@Override
	public void run() {
		// TODO Auto-generated method stub
		for (int i = 0; i < 10; i++) {
			System.out.println("线程开始：" + name + ",i=" + i);
		}
	}
	public ImpRunnable(String name){
		this.name = name;
	}
	public static void main(String[] args) {
		ImpRunnable imp = new ImpRunnable("线程a");
		ImpRunnable imp2 = new ImpRunnable("线程b");
		new Thread(imp).start();
		new Thread(imp2).start();
	}

}

推荐使用实现Runnable接口，因为java单继承，但是可以实现多个接口，而且Runnable会使资源共享

package com.hgf.thread;

public class ThreadTicket extends Thread {
	private int ticket = 10;

	public void run() {
		for (int i = 0; i < 20; i++) {
			if (this.ticket > 0) {
				System.out.println("卖票：ticket" + ticket--);
			}
		}
	}
	public static void main(String[] args) {  
		ThreadTicket mt1=new ThreadTicket();  
		ThreadTicket mt2=new ThreadTicket();  
		ThreadTicket mt3=new ThreadTicket();  
		mt1.start();//每个线程都各卖了10张，共卖了30张票  
		mt2.start();//但实际只有10张票，每个线程都卖自己的票  
		mt3.start();//没有达到资源共享  
		}  
}

package com.hgf.thread;

public class ThreadTicket implements Runnable {
	private int ticket = 10;

	public void run() {
		for (int i = 0; i < 20; i++) {
			if (this.ticket > 0) {
				System.out.println("卖票：ticket" + ticket--);
			}
		}
	}

	public static void main(String[] args) {
		ThreadTicket mt=new ThreadTicket();  
		new Thread(mt).start();//同一个mt，但是在Thread中就不可以，如果用同一  个实例化对象mt，就会出现异常  
		new Thread(mt).start();
		new Thread(mt).start();  
	}
}