main執行緒類：

public class DemoThreadLocal {
    public static void main(String[] args) {
        ThreadLocal<String> tl = new ThreadLocal<>();

        //獲取當前main執行緒物件繫結的值
        String s = tl.get();
        System.out.println(s);  //null

        //給當前main執行緒物件繫結值
        tl.set("hello ThreadLocal");
        String s1 
 
= tl.get();
        System.out.println(s1); //hello ThreadLocal

        //開啟一個新執行緒
        SubThread subThread = new SubThread(tl);
        subThread.start();
    }
}

subThread執行緒類：

public class SubThread extends Thread {
    private ThreadLocal<String> tl;

    public SubThread(ThreadLocal tl){
        
 
this.tl = tl;
    }

    @Override
    public void run() {
        //獲取當前執行緒物件上繫結的值
        String s = tl.get();
        System.out.println("當前執行緒物件繫結的值："+s);    //當前執行緒物件繫結的值：null

        tl.set("蕪湖");
        String s1 = tl.get();
        System.out.println("當前執行緒物件繫結的值："+s1);   //當前執行緒物件繫結的值：蕪湖
    }
}