生产者消费者实现的几种方式

-----------------------------使用 synchronized  + wait + nofify ---------------------
package com.example.demo;
/**
 * @author yangxj
 * @date 2019-10-14 10:01
 */
public class TestMockDemo {

      Object lock = new Object();

      volatile boolean flag = true; // 是否需要开始生产的标记


    public void product() {
        for (int i = 0; i < 10; i++) {
                synchronized (lock) {
                   if (flag) {
                       System.out.println("生产: 蛋糕" + i);
                       flag = false;
                       lock.notify(); // 通知消费
                   }
                    try {
                        lock.wait(); // 等待消费
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        }

    public void consume(){
        for (int i = 0; i < 10; i++) {
            synchronized (lock) {
                if (flag) {
                    try {
                        lock.wait(); // 等待生产
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                System.out.println("消费: 蛋糕" + i);
                flag = true;
                lock.notify(); // 通知生产
        }
        }
    }
    public static void main(String[] args) {
        TestMockDemo demo = new TestMockDemo();
        new Thread(demo::product).start();
        new Thread(demo::consume).start();
    }
}


-----------------------------------------使用 lock + await + signal ----------------------------------

package com.example.demo;

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

/**
 * @author yangxj
 * @date 2019-10-14 10:01
 */
public class TestMockDemo {

    ReentrantLock lock = new ReentrantLock();
    Condition condition = lock.newCondition();
    
    volatile boolean flag = true; // 是否需要开始生产的标记


    public void product() {
        for (int i = 0; i < 10; i++) {
            try {
                lock.lock();
                if (flag) {
                    System.out.println("生产: 蛋糕" + i);
                    flag = false;
                    condition.signal(); // 通知消费
                }
                try {
                    condition.await(); // 等待消费
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            } finally {
                lock.unlock();
            }
        }
    }

    public void consume() {
        for (int i = 0; i < 10; i++) {
            try {
                lock.lock();
                if (flag) {
                    try {
                        condition.await();  //等待生产
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                System.out.println("消费: 蛋糕" + i);
                flag = true;
                condition.signal(); // 通知生产

            } finally {
                lock.unlock();
            }
        }
    }

    public static void main(String[] args) {
        TestMockDemo demo = new TestMockDemo();
        new Thread(demo::product).start();
        new Thread(demo::consume).start();
    }
}

---------------------- 使用阻塞队列  BlockingQueue-----------

package com.example.demo;

import java.util.concurrent.BlockingQueue;
import java.util.concurrent.SynchronousQueue;

/**
 * @author yangxj
 * @date 2019-10-14 10:01
 */
public class TestMockDemo {

     BlockingQueue queue = new SynchronousQueue<String>(); // 阻塞队列


    public void product() {
        for (int i = 0; i < 10; i++) {
            try {
                queue.put(i);
                System.out.println("生产: 蛋糕" + i);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    public void consume() {
        for (int i = 0; i < 10; i++) {
            try {
                queue.take();
                System.out.println("消费: 蛋糕" + i);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) {
        TestMockDemo demo = new TestMockDemo();
        new Thread(demo::product).start();
        new Thread(demo::consume).start();
    }
}