不同线程不能获取其他线程设置的ThreadLocal里面的值
背景:
最近在项目用到了ThreadLocal,存放一些值。起线程异步获取ThreadLocal中的值,得到null。这是由于,ThreadLocal.get()会获取当前线程的一个map对象,以ThreadLocal为key获取对象。
demo:
这里定义了一个Person类,使用两个线程,一个向threadlocal set(),两个线程都使用threadLocal.get()获取存放的对象
其中一个线程没有获取到值
/** * Created by GuanXF on 2017/12/8. */ public class ThreadLocalTest { private static ThreadLocal<Person> personThreadLocal = new ThreadLocal<Person>(); public static void main(String[] args) throws InterruptedException { Thread t1 = new Thread(new Runnable() { public void run() { Person gxf = new Person("Gxf", 18); personThreadLocal.set(gxf); System.out.println("From threadlocal : " + personThreadLocal.get()); } }); Thread t2 = new Thread(new Runnable() { public void run() { System.out.println("From threadlocal : " + personThreadLocal.get()); } }); t1.start(); t1.join(); t2.start(); } //Person实体类 static class Person{ private String name; private int age; public Person(String name, int age) { this.name = name; this.age = 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; } @Override public String toString() { return "Person{" + "name='" + name + '\'' + ", age=" + age + '}'; } } }
Please call me JiangYouDang!