package fuxi.concurrency;

import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * @Description: 生产者消费者模式
 * @author 张文军
 * @Company: njauit.cn
 * @version: 1.0
 * @date 2020/7/1913:08
 */
class ProducerConsumer {
    public void prod() {
        System.out.println("prod");
    }

    public void consume() {
        System.out.println("consume");
    }
}

/**
 * @author user
 */
public class ProducerConsumerTest {
    /**
     * 需要注意的是：如果需要有序执行，就需要设置一个标志位，并且要循环检测标志位的变化情况；
     */
    private static Lock lock = new ReentrantLock();
    private Condition condition = lock.newCondition();
    private AtomicBoolean flag = new AtomicBoolean(true);


    /**
     * 使用Synchronized 方式；
     *
     * 注意：需要在调用wait()或者notify()之前，必须使用synchronized语义绑定住被wait/notify的对象
     *     （即：被Synchronized绑定的对象和调用 notify()/notifyAll()的对象是同一个）
     */
    public void ProductCustomerTest() {
        new Thread(() -> {
            // TODO:
            ProducerConsumer producerConsumer = new ProducerConsumer();
            for (int i = 0; i < 20; i++) {
                synchronized (flag) {
                    while (!flag.get()) {
                        try {
                            flag.wait();
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }

                    producerConsumer.prod();
                    flag.set(!flag.get());
                    flag.notifyAll();
                }
            }
        }, "ProducerConsumerTest-1").start();

        new Thread(() -> {
            // TODO:
            ProducerConsumer producerConsumer = new ProducerConsumer();
            for (int i = 0; i < 20; i++) {
                synchronized (flag) {
                    while (flag.get()) {
                        try {
                            flag.wait();
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }

                    producerConsumer.consume();
                    flag.set(!flag.get());
                    flag.notifyAll();
                }
            }
        }, "ProducerConsumerTest-2").start();

    }

    /**
     * 使用Look和Condition ；
     */
    public void conditionTest() {
        new Thread(() -> {
            // TODO:
            ProducerConsumer producerConsumer = new ProducerConsumer();
            for (int i = 0; i < 20; i++) {
                lock.lock();
                try {
                    while (!flag.get()) {
                        try {
                            condition.await();
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }

                    producerConsumer.prod();
                    flag.set(!flag.get());
                    condition.signalAll();
                } catch (Exception e) {
                    e.printStackTrace();
                } finally {
                    lock.unlock();
                }

            }
        }, "ProducerConsumerTest-1").start();


        new Thread(() -> {
            // TODO:
            ProducerConsumer producerConsumer = new ProducerConsumer();
            for (int i = 0; i < 20; i++) {
                lock.lock();
                try {
                    while (flag.get()) {
                        try {
                            condition.await();
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }

                    producerConsumer.consume();
                    flag.set(!flag.get());
                    condition.signalAll();
                } catch (Exception e) {
                    e.printStackTrace();
                } finally {
                    lock.unlock();
                }

            }
        }, "ProducerConsumerTest-2").start();

    }

    public static void main(String[] args) {
        ProducerConsumerTest producerConsumerTest = new ProducerConsumerTest();
        //producerConsumerTest.ProductCustomerTest();
        producerConsumerTest.conditionTest();
    }


}