ThreadLocal实现：java线程范围内的共享数据,线程外独立

标签：java   多线程   共享数据   threadlocal   

场景应用：银行转账时，A给B转账，C给D转账。两者都是调用的connection.begainTransaction();connection.commit();

如何才能保证A,B同在一个线程中，C、D同在一个线程中，且A,BC,D在线程内共享，在线程外独立。

方法一，Map<Thread, Integer>实现:

/**
 * 线程范围内的共享数据
 */
package cn.itcast.lesson5;

import java.util.HashMap;
import java.util.Map;
import java.util.Random;

public class TestThreadLocal {
	private static int data = 0;
	private static Map<Thread, Integer> threadData = new HashMap<Thread, Integer>();
	public static void main(String[] args){
		//产生两个线程数据
		for(int i=0;i<2;i++){
			new Thread(new Runnable() {
				
				public void run() {
					 int data = new Random().nextInt();
					System.out.println(Thread.currentThread().getName()
							+" has put data"+data);
					//将线程的数据以key,value的形式存储
					threadData.put(Thread.currentThread(), data);
				new A().get();
				new B().get();
				}
			}).start();
	}
	}
	static class A{
		public void get(){
			int data = threadData.get(Thread.currentThread());
			System.out.println("A from " + Thread.currentThread().getName()
					+" get data" + data);
		}
	}
	static class B{
		public void get(){
			int data = threadData.get(Thread.currentThread());
			System.out.println("B from " + Thread.currentThread().getName()
					+" get data" + data);
		}
	}
}<span style="color:#ff0000;">
</span>

方法二，ThreadLocal实现：

package cn.itcast.lesson5;
import java.util.Random;
public class ThreadLocal11 {
	
	private static ThreadLocal<Integer> x = new ThreadLocal<Integer>();
	public static void main(String[] args){
		//产生两个线程数据
		for(int i=0;i<2;i++){
			new Thread(new Runnable() {
				
				public void run() {
					 int data = new Random().nextInt();
					System.out.println(Thread.currentThread().getName()
							+" has put data"+data);
					//将线程的数据以key,value的形式存储
					x.set(data);
				new A().get();
				new B().get();
				}
			}).start();
	}
	}
	static class A{
		public void get(){
			int data =x.get();
			System.out.println("A from " + Thread.currentThread().getName()
					+" get data" + data);
		}
	}
	static class B{
		public void get(){
			int data =x.get();
			System.out.println("B from " + Thread.currentThread().getName()
					+" get data" + data);
		}
	}
}

ThreadLocal实现：java线程范围内的共享数据,线程外独立,布布扣,bubuko.com

ThreadLocal实现：java线程范围内的共享数据,线程外独立

标签：java   多线程   共享数据   threadlocal   

原文地址：http://blog.csdn.net/u014078192/article/details/29367849