/*

 * 2015/8/6 ：                         不刻意为自己寻找存在感

 * 目的：初步了解线程范围内共享变量的概念

 * 有点问题：

 *      有时会输出Null

 * 问题的原因：

 * 		可能HashMap线程不安全导致的

 * 		

 */

public class ShareData1 {

	//static int data = 0;

	static Map<Thread,Integer> map = new HashMap<Thread,Integer>();

	public static void main(String[] args) {

		

		for(int i=0;i<2;i++){

			new Thread(){

				public void run() {

					int data = new Random().nextInt();

					System.out.println(Thread.currentThread().getName()+":"+data);

					map.put(Thread.currentThread(), data);

				/*	map.put(Thread.currentThread(), data);

					System.out.println(Thread.currentThread().getName()+":"+data);*/

					

					new A().getDataA();

					new B().getDataB();

				};

			}.start();

		}

	}

	static class A{

	void getDataA(){

		System.out.println(Thread.currentThread().getName()+"A:"+map.get(Thread.currentThread()));

	}}

	static class B{

	void getDataB(){

		System.out.println(Thread.currentThread().getName()+"B:"+map.get(Thread.currentThread()));

	}}

}



/*错误的结果:

	Thread-1:-236229789

	Thread-0:-934142735

	Thread-1A:null

	Thread-0A:-934142735

	Thread-1B:null

	Thread-0B:-934142735

	=====================

	Thread-0:-1331897743

	Thread-1:-1239048981

	Thread-1A:-1239048981

	Thread-0A:null

	Thread-1B:-1239048981

	Thread-0B:null

	====================

	Thread-0:-1192204428

	Thread-1:-439715298

	Thread-0A:null

	Thread-1A:-439715298

	Thread-0B:null

	Thread-1B:-439715298

******************************************************

  正确的结果

	Thread-0:1109365405

	Thread-1:969714427

	Thread-0A:1109365405

	Thread-1A:969714427

	Thread-0B:1109365405

	Thread-1B:969714427

	===================

	Thread-1:1936099369

	Thread-0:-616837039

	Thread-0A:-616837039

	Thread-1A:1936099369

	Thread-0B:-616837039

	Thread-1B:1936099369

*/