Java中synchronized和ReentrantLock的锁的本质区别

抛开面试八股文不谈，两种都本质区别是线程获取不到锁时的状态区别。
Talk is cheap, show my code！

public class Main20 {

    private static ReentrantLock lock = new ReentrantLock();

    public static void main(String[] args) throws Exception {
        test();
    }

    public static void test() throws InterruptedException {
        Thread thread01 = new Thread(Main20::fun01);
        Thread thread02 = new Thread(Main20::fun02);
        Thread thread11 = new Thread(Main20::fun01);
        Thread thread12 = new Thread(Main20::fun02);
        
        thread01.start(); //线程先占着资源
        thread02.start(); //线程先占着资源
        TimeUnit.MILLISECONDS.sleep(1);
        System.out.println("step01: " + thread01.getState()); //step01: RUNNABLE
        System.out.println("step01: " + thread02.getState()); //step01: RUNNABLE
        System.out.println("step01: " + thread11.getState()); //step01: NEW
        System.out.println("step01: " + thread12.getState()); //step01: NEW
        thread11.start(); //线程抢夺资源
        thread12.start(); //线程抢夺资源
        TimeUnit.MILLISECONDS.sleep(1);
        System.out.println("step02: " + thread01.getState()); //step02: RUNNABLE
        System.out.println("step02: " + thread02.getState()); //step02: RUNNABLE
        System.out.println("step02: " + thread11.getState()); //step02: BLOCKED
        System.out.println("step02: " + thread12.getState()); //step02: WAITING
        thread01.interrupt(); //终止原线程
        thread02.interrupt(); //终止原线程
        TimeUnit.MILLISECONDS.sleep(1);
        System.out.println("step03: " + thread01.getState()); //step03: TERMINATED
        System.out.println("step03: " + thread02.getState()); //step03: TERMINATED
        System.out.println("step03: " + thread11.getState()); //step03: RUNNABLE
        System.out.println("step03: " + thread12.getState()); //step03: RUNNABLE
    }
    
    public synchronized static void fun01() {
        long i = -100000000000L;
        while (true) {
            i++;
            if (Thread.currentThread().isInterrupted()) {
                break;
            }
        }
    }

    public static void fun02() {
        lock.lock();
        long i = -100000000000L;
        while (true) {
            i++;
            if (Thread.currentThread().isInterrupted()) {
                break;
            }
        }
        lock.unlock();
    }
}

结果

这两状态的本质区别，blocked是主动，waiting是被动。blocked主动寻找监视器继续竞争锁，waiting需要被动通知继续执行。blocked受操作系统控制，waiting受JVM控制。

若有错误或者异议，欢迎指出～