java夯实基础-多线程

小鱼儿 2022-06-07 09:49 220阅读 0赞

本文总结java中多线程

1、线程的创建

package com.wllfengshu.test;
    
    import org.junit.Test;
    /**
     * 线程的创建Thread
     * 线程四种状态：新建、运行、中断、死亡
     */
    public class Test1线程创建 {
    	//线程创建
    	@Test
    	public void test1(){
    		A a=new A();
    		Thread b=new Thread(new B());
    		a.start();
    		b.start();
    		while(true){//主线程也在死循环
    			System.out.println("Main");
    		}
    	}
    	//线程常用方法
    	@Test
    	public void test2(){
    		A a=new A();
    		System.out.println(a.isAlive());//线程是否在运行状态
    		a.start();//开启线程
    		System.out.println(a.getName());//获取线程名族
    		while(true){//主线程也在死循环
    			System.out.println("Main");
    			try {
    				Thread.sleep(1000);//睡觉
    			} catch (InterruptedException e) {
    				e.printStackTrace();
    			}
    			System.out.println("此时占用CUP的线程是："+Thread.currentThread());//此时占用CUP的线程
    		}
    		
    	}
    }
    class A extends Thread{//继承Thread类
    	@Override
    	public void run() {
    		while(true){
    			try {
    				Thread.sleep(1000);//睡觉
    			} catch (InterruptedException e) {
    				e.printStackTrace();
    			}
    			System.out.println(" A ");
    		}
    	}
    }
    class B implements Runnable{//实现Runnable接口
    	@Override
    	public void run() {
    		while(true){
    			System.out.println(" B ");
    		}
    	}
    }

2、线程同步

package com.wllfengshu.test;
    
    import org.junit.Test;
    
    public class Test2线程同步 {
    	@Test
    	public void test1(){
    		Bank bank=new Bank();
    		Thread kuaiji=new Thread(bank);
    		kuaiji.setName("会计");
    		Thread chuna=new Thread(bank);
    		chuna.setName("出纳");
    		kuaiji.start();
    		chuna.start();
    	}
    }
    class Bank implements Runnable{
    	private int money=0;
    	public synchronized void addOrSub(int n){
    		if (Thread.currentThread().getName().equals("会计")) {
    			for (int i = 0; i < 3; i++) {
    				money+=n; 
    				System.out.println(Thread.currentThread().getName()+"做了加法运算"+money+"，睡觉了");
    				try {
    					Thread.sleep(1000);
    				} catch (InterruptedException e) {
    					e.printStackTrace();
    				}
    			}
    		}else if (Thread.currentThread().getName().equals("出纳")){
    			for (int i = 0; i < 3; i++) {
    				money-=n;
    				System.out.println(Thread.currentThread().getName()+"做了减法运算"+money+"，睡觉了");
    				try {
    					Thread.sleep(1000);
    				} catch (InterruptedException e) {
    					e.printStackTrace();
    				}
    			}
    		}	
    	}
    	@Override
    	public void run() {
    		if (Thread.currentThread().getName().equals("会计")) {
    			addOrSub(8);//加
    		}else if (Thread.currentThread().getName().equals("出纳")){
    			addOrSub(5);//减
    		}	
    	}
    }

3、Wait和notify

package com.wllfengshu.test;
    
    public class Test3Wait和notify {
    	//售票员没有零钱    每张票5元
    	//张一用一张10的去买票，等
    	//张二用一张5元的买票，问题解决
    	public static void main(String[] args) {
    		Tick tick=new Tick();
    		Thread zhangOne= new Thread(tick);
    		zhangOne.setName("张一");
    		Thread zhangTwo= new Thread(tick);
    		zhangTwo.setName("张二");
    		zhangTwo.start();
    		zhangOne.start();
    	}
    }
    class Tick implements Runnable{
    	private int saler=0;//售票员
    	public synchronized void saleTick(int money){
    		if (money==5) {
    			System.out.println(Thread.currentThread().getName()+"的钱正好，给他卖票了");
    			saler+=5;
    		}else if(money==10){
    			while(saler<5){
    				try {
    					System.out.println(Thread.currentThread().getName()+"给的10元，不能买票，等待");
    					wait();
    				} catch (InterruptedException e) {
    					e.printStackTrace();
    				}
    			}
    			saler+=10;
    			System.out.println(Thread.currentThread().getName()+"给他卖票了");
    		}
    		notifyAll();
    	}
    	@Override
    	public void run() {
    		if (Thread.currentThread().getName().equals("张一")) {
    			saleTick(5);
    		}else if (Thread.currentThread().getName().equals("张二")){
    			saleTick(10);
    		}
    	}
    }