JAVA线程通信之生产者与消费者

Posted 2020-10-06 思余生

package cn.test.hf.test3;

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

public class FactoryUtils {

    private Resource resource;
    private int producerId = 1;

    // 可重入锁
    ReentrantLock lock = new ReentrantLock();
    Condition ProducersCondition = lock.newCondition();

    Condition customerLockCondition = lock.newCondition();

    FactoryUtils() {

        resource = new Resource();

        resource.setId(0);
        resource.setFlag(true);
    }

    /**
     * 生产
     */
    public void ProducerResource() {

        lock.lock();
        // 使用锁机制
        try {

            while (true) {

                while (!resource.isFlag()) {

                    // 还未消费，将线程等待
                    System.out.println("生产者等待");
                    // 使用condition通知同组的等待
                    ProducersCondition.await();
                }

                // 生产
                resource.setId(producerId++);
                resource.setFlag(false);
                System.out.println("生产者线程" + Thread.currentThread().getName() + "生产了ID为" + resource.getId() + "的产品");
                // 延时一秒好看结果
                Thread.sleep(1000);
                // 生产完后通知消费者线程
                System.out.println("通知消费者");
                customerLockCondition.signalAll();
            }
        } catch (Exception e) {

            e.printStackTrace();
        } finally {

            // 释放锁
            lock.unlock();
        }
    }

    /**
     * 生产
     */
    public synchronized void customer() {

        lock.lock();
        try {
            while (true) {

                // 消费者等待
                while (resource.isFlag()) {

                    customerLockCondition.await();
                }

                // 设置为已消费
                resource.setFlag(true);
                System.out.println("消费者线程" + Thread.currentThread().getName() + "消费了ID为" + resource.getId() + "的产品");
                // 延时一秒好看结果
                Thread.sleep(1000);
                // 消费完后通知生产者线程生产
                System.out.println("通知生产者");
                ProducersCondition.signalAll();
            }
        } catch (Exception e) {

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