笔记，线程的等待，生产者和消费者

Posted 2021-06-06 就今天呐

package com.kaikeba.test4_6;


/**
 * @Author buxh
 * @Date 2021/6/5 23:05
 **/
public class task1 {
    public static void main(String[] args) {
//        生产和消费
        Subject subject = new Subject();
        new Teacher(subject).start();
        new Student(subject).start();

    }

    static class Subject{
        private String name ;
        private boolean flag = true;

        public synchronized void satrtClass(String name){
            if (flag){
                this.name = name;
                try {
                    Thread.sleep(2000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                System.out.println(name + "上课了");

                flag = false;
                this.notifyAll();
                try {
                    this.wait();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
        public synchronized void rest(){
            if (!flag){
                try {
                    Thread.sleep(4000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                System.out.println(name + "下课了");
                flag = true;
                this.notifyAll();
                try {
                    this.wait();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }

    }

    static class Student extends Thread{
        private Subject subject;
        public Student(Subject subject){
            this.subject = subject;
        }

        @Override
        public void run() {
            for (int i = 0;i<100;i++){
                if(i%2==0) {
                    subject.satrtClass("英语课");
                }else {
                    subject.satrtClass("体育课");
                }
            }
        }
    }
    static class Teacher extends Thread{
        private Subject subject;
        public Teacher(Subject subject){
            this.subject = subject;
        }

        @Override
        public void run() {

            for (int i = 0;i<100;i++) {
                try {
                    Thread.sleep(3000);
                    subject.rest();

                } catch (InterruptedException e) {
                    e.printStackTrace();
                }

            }
        }
    }


}

进程 是指一个内存中运行的应用程序，每个进程都有一个独立的内存空间 

线程 是进程中的一个执行路径，共享一个内存空间，线程之间可以自由切换，并发执行. 一个进程最少 有一个线程 线程实际上是在进程基础之上的进一步划分，一个进程启动之后，里面的若干执行路径又可以划分 成若干个线程