为什么main线程会解锁lock和synchronized

Question

  public static void main(String[] args) {
        Lock rl = new ReentrantLock();

        try {

            rl.lock();
            System.out.println("--1" + rl);
            rl.lockInterruptibly();
            System.out.println("--2" + rl);
            rl.lock();
            // rl.lockInterruptibly();
            synchronized (rl) {
                System.out.println("--3" + rl);
            }
            System.out.println("--4" + rl);
        } catch (InterruptedException e) {

            e.printStackTrace();
        } finally {
            // 解锁
            // rl.unlock();
            // rl.unlock();

        }

    }

}

}

把unlock注释掉,输出lock的状态,发现被main线程解锁了,
为什么main线程会解锁

Answer 1

因为main是主线程