public static void threadLocal() {
        ThreadLocal<String> local = new ThreadLocal<>();

        IntStream.range(0, 10).forEach(i -> new Thread(() -> {
            local.set(Thread.currentThread().getName() + ":" + i);
            System.out.println("线程：" + Thread.currentThread().getName() + ",local:" + local.get());
        }).start());
    }		
		
		

		
package cn.netkiller.thread;

public class ThreadLocaTest {

    private static ThreadLocal<String> local = new ThreadLocal<String>();
    public static void main(String[] args) throws InterruptedException {

        new Thread(new Runnable() {
            public void run() {
                System.out.println(Thread.currentThread().getName() + "：" + local.get());
                ThreadLocaTest.local.set("thread_A");
                System.out.println(Thread.currentThread().getName() + "：" + local.get());
            }
        }, "A").start();

        Thread.sleep(1000);

        new Thread(new Runnable() {
            public void run() {
                System.out.println(Thread.currentThread().getName() + "：" + local.get());
                ThreadLocaTest.local.set("thread_B");
                System.out.println(Thread.currentThread().getName() + "：" + local.get());
                local.remove();
                System.out.println("remove: " + local.get());
            }
        }, "B").start();
    }
}		
		
		

		
package cn.netkiller.test;

public class Test {
    public static void main(String[] args) {
        System.out.println(Thread.currentThread());

        try (var ctx = new UserContext("Bob")) {
            // 可任意调用UserContext.currentUser():
            String currentUser = UserContext.currentUser();
            System.out.println(currentUser);
        } // 在此自动调用UserContext.close()方法释放ThreadLocal关联对象

    }

    public static class UserContext implements AutoCloseable {

        static final ThreadLocal<String> ctx = new ThreadLocal<>();

        public UserContext(String user) {
            ctx.set(user);
        }

        public static String currentUser() {
            return ctx.get();
        }

        @Override
        public void close() {
            ctx.remove();
        }
    }
}