概述

通過加鎖、解鎖，鎖住一段程式碼塊

例項

/**
 * 鎖
 */
public class TestLock {
    public static void main(String[] args) {
        MyLock myLock1 = new MyLock();
        Thread t1 = new Thread(myLock1);
        Thread t2 = new Thread(myLock1);
        Thread t3 = new Thread(myLock1);
        t1.start();
        t2.start();
        t3.start();
    }
}
class MyLock implements Runnable {
    private int ticket = 10;
    private final ReentrantLock lock = new ReentrantLock();
    @Override
    public void run() {
        while (true){

            try {
                lock.lock();
                if(ticket <= 0){
                    return;
                }
                Thread.sleep(1000);
                System.out.println(Thread.currentThread().getName()+"拿到了票 ： "+ticket--);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }finally {
                lock.unlock();
            }

        }
    }
}