ThreadLocal类及应用技巧; 实现线程范围内数据共享_JAVA_编程开发_程序员俱乐部

class="java" name="code">public class ThreadTest6 {
	
	private static ThreadLocal<Integer> currentLocalThread = 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);
							
							currentLocalThread.set(data);
							//获取与本线程相关的实例
							MyThreadScopeData myData = MyThreadScopeData.getThreadInstance();
							myData.setName("name" + data);
							myData.setAge(data);
							
							//存入当前线程中
							myThreadScopeData.set(myData);
							
							new A().get();
							new B().get();
						}
					}
			).start();
		}
	}


	static class A{
		public void get(){
			//int data = localThreadMap.get(Thread.currentThread());
			int data = currentLocalThread.get();
			System.out.println("A from  " + Thread.currentThread().getName() + " get data :" + data);
			//获取与本线程相关的实例
			//MyThreadScopeData myData = MyThreadScopeData.getThreadInstance();
			//从当前线程中获取
			MyThreadScopeData myData = myThreadScopeData.get();
			System.out.println("A from  " + Thread.currentThread().getName()
					+ " getName ：" + myData.getName() 
					+ " , getAge : " + myData.getAge());
		}
	}
	static class B{
		public void get(){
			//int data = localThreadMap.get(Thread.currentThread());
			int data = currentLocalThread.get();
			System.out.println("B from  " + Thread.currentThread().getName() + " get data :" + data);
			//获取与本线程相关的实例
			//MyThreadScopeData myData = MyThreadScopeData.getThreadInstance();
			//从当前线程中获取
			MyThreadScopeData myData = myThreadScopeData.get();
			System.out.println("B from  " + Thread.currentThread().getName()
					+ " getName ：" + myData.getName() 
					+ " , getAge : " + myData.getAge());
		}
	}
}

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

?

?

打印结果：

Thread-1 has put data : -1091157391

Thread-0 has put data : -1297198387

A from ?Thread-1 get data :-1091157391

A from ?Thread-1 getName ：name-1091157391 , getAge : -1091157391

A from ?Thread-0 get data :-1297198387

A from ?Thread-0 getName ：name-1297198387 , getAge : -1297198387

B from ?Thread-0 get data :-1297198387

B from ?Thread-0 getName ：name-1297198387 , getAge : -1297198387

B from ?Thread-1 get data :-1091157391

B from ?Thread-1 getName ：name-1091157391 , getAge : -1091157391

?