package com.wkcto.lock.reentrant;

import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * Lock鎖的基本使用
 */
public class Test02 {
    //定義顯示鎖
    static Lock lock = new ReentrantLock();
    //定義方法
    public static void sm(){
        //先獲得鎖
        lock.lock();
        //for循環就是同步代碼塊
        for (int i = 0; i < 100; i++) {
            System.out.println(Thread.currentThread().getName() + " -- " + i);
        }
        //釋放鎖
        lock.unlock();
    }

    public static void main(String[] args) {
        Runnable r = new Runnable() {
            @Override
            public void run() {
                sm();
            }
        };
        //啟動三個線程
        new Thread(r).start();
        new Thread(r).start();
        new Thread(r).start();
    }
}

package com.wkcto.lock.reentrant;

import java.util.Random;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * 使用Lock鎖同步不同方法中的同步代碼塊
 */
public class Test03 {
    static Lock lock = new ReentrantLock();         //定義鎖對象
    public static void sm1(){
        //經常在try代碼塊中獲得Lock鎖, 在finally子句中釋放鎖
        try {
            lock.lock();        //獲得鎖
            System.out.println(Thread.currentThread().getName() + "-- method 1 -- " + System.currentTimeMillis() );
            Thread.sleep(new Random().nextInt(1000));
            System.out.println(Thread.currentThread().getName() + "-- method 1 -- " + System.currentTimeMillis() );
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();          //釋放鎖
        }
    }

    public static void sm2(){
        try {
            lock.lock();        //獲得鎖
            System.out.println(Thread.currentThread().getName() + "-- method 22 -- " + System.currentTimeMillis() );
            Thread.sleep(new Random().nextInt(1000));
            System.out.println(Thread.currentThread().getName() + "-- method 22 -- " + System.currentTimeMillis() );
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();          //釋放鎖
        }
    }

    public static void main(String[] args) {
        Runnable r1 = new Runnable() {
            @Override
            public void run() {
                sm1();
            }
        };
        Runnable r2 = new Runnable() {
            @Override
            public void run() {
                sm2();
            }
        };

        new Thread(r1).start();
        new Thread(r1).start();
        new Thread(r1).start();
        new Thread(r2).start();
        new Thread(r2).start();
        new Thread(r2).start();
    }
}