ThreadLocal类 线程间共享变量的应用

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


public class ThreadLocalTest {


private static ThreadLocal<Integer> x = new ThreadLocal<Integer>();
private static ThreadLocal<MyThreadScopeData> myThreadScopeData = new ThreadLocal<MyThreadScopeData>();
public static void main(String[] args) {
for(int i=0;i<2;i++){
new Thread(new Runnable(){
@Override
public void run() {
int data = new Random().nextInt();
System.out.println(Thread.currentThread().getName() 
+ " has put data :" + data);
x.set(data);
/* MyThreadScopeData myData = new MyThreadScopeData();
myData.setName("name" + data);
myData.setAge(data);
myThreadScopeData.set(myData);*/
MyThreadScopeData.getThreadInstance().setName("name" + data);
MyThreadScopeData.getThreadInstance().setAge(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);
/* MyThreadScopeData myData = myThreadScopeData.get();;
System.out.println("A from " + Thread.currentThread().getName() 
+ " getMyData: " + myData.getName() + "," +
myData.getAge());*/
MyThreadScopeData myData = MyThreadScopeData.getThreadInstance();
System.out.println("A from " + Thread.currentThread().getName() 
+ " getMyData: " + myData.getName() + "," +
myData.getAge());
}
}

static class B{
public void get(){
int data = x.get();
System.out.println("B from " + Thread.currentThread().getName() 
+ " get data :" + data);
MyThreadScopeData myData = MyThreadScopeData.getThreadInstance();
System.out.println("B from " + Thread.currentThread().getName() 
+ " getMyData: " + myData.getName() + "," +
myData.getAge());
}
}
}


class MyThreadScopeData{
private MyThreadScopeData(){}
public static /*synchronized*/ MyThreadScopeData getThreadInstance(){
MyThreadScopeData instance = map.get();
if(instance == null){
instance = new MyThreadScopeData();
map.set(instance);
}
return instance;
}
//private static MyThreadScopeData instance = null;//new MyThreadScopeData();
private static ThreadLocal<MyThreadScopeData> map = new ThreadLocal<MyThreadScopeData>();

private String name;
private int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}