[Java手撕]生产者消费者模型

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

public class Main {

    public static final Queue<Integer> message = new LinkedList<>();

    public static ReentrantLock lock = new ReentrantLock();
    public static Condition writeable = lock.newCondition();
    public static Condition readable = lock.newCondition();


    public static void main(String[] args) {


        Thread thread1 = new Thread(new Runnable() {
            @Override
            public void run() {
                System.out.println("生产者开始运行");
                for (int i = 0; i <= 20; i++) {
                    lock.lock();
                    try {
                        System.out.println("生产者取得队列所有权=======");
                        while (message.size() >= 10) {
                            try {
                                System.out.println("队列中已经有10个消息，生产者阻塞");
                                writeable.await();
                                System.out.println("队列恢复可写，生产者唤醒");
                            } catch (InterruptedException e) {
                                throw new RuntimeException(e);
                            }
                        }
                        if (i == 20) {
                            System.out.println("生产者产生结束信号");
                            message.add(-1);
                            System.out.println("生产者运行结束");
                            readable.signal();
                            break;
                        } else {
                            System.out.println("生产者向队列写入 " + i);
                            message.add(i);
                            System.out.println("唤醒消费者");
                            readable.signal();
                        }
                    } finally {
                        lock.unlock();

                    }
                }
            }
        });


        Thread thread2 = new Thread(new Runnable() {
            @Override
            public void run() {
                System.out.println("消费者开始运行");
                while (true) {
                    lock.lock();
                    System.out.println("消费者取得队列所有权=======");
                    try {

                        while (message.isEmpty()) {
                            try {
                                System.out.println("消费者等待队列可读");
                                readable.await();
                                System.out.println("消费者恢复可读");
                            } catch (InterruptedException e) {
                                throw new RuntimeException(e);
                            }
                        }
                        Integer a = message.poll();
                        if (a == -1) {
                            System.out.println("消费者读到结束信号，消费者结束");
                            break;
                        }
                        System.out.println("从队列读出 " + a);
                        System.out.println("唤醒生产者");
                        writeable.signal();
                    } finally {
                        lock.unlock();

                    }
                }
                System.out.println("消费者运行结束");
            }
        });

        thread1.start();
        thread2.start();


    }

}