第一篇多线程

Posted 2021-01-04 zhangzhipeng001

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 1 package com.zzp.thread;
 2 /**
 3  * 
 4  * 创建线程：方式一
 5  * 1、继承thread类，重写run方法
 6  * 2、启动线程，调用start方法
 7  * 
 8  * @author java
 9  *
10  */
11 public class StartThread extends Thread{
12     //重写run()
13     @Override
14     public void run() {
15         for(int i=0;i<10;i++){
16             System.out.println("一边学习");
17         }
18     }
19 
20     public static void main(String[] args) {
21         //创建Thread子类对象
22         StartThread st = new StartThread();
23         //启动，并不是立即启动，而是等待cpu调用，至于CPU何时调用，不知道
24         //开启线程的时机很重要
25         st.start();
26         //如果直接调用run()方法，则是普通方法调用，不是开启多线程
27         //st.run();
28         
29         for(int i=0;i<10;i++){
30             System.out.println("一边听歌");
31         }
32     }
33 }

 1 package com.zzp.thread;
 2 
 3 import java.io.File;
 4 import java.io.IOException;
 5 import java.net.MalformedURLException;
 6 import java.net.URL;
 7 
 8 import org.apache.commons.io.FileUtils;
 9 
10 /**
11  * 
12  * 下载工具类
13  * @author java
14  *
15  */
16 public class WebDownLoader {
17     public void downLoader(String url,String name){
18         try {
19             FileUtils.copyURLToFile(new URL(url), new File(name));
20         } catch (MalformedURLException e) {
21             e.printStackTrace();
22         } catch (IOException e) {
23             e.printStackTrace();
24         }
25     }
26 }

 1 package com.zzp.thread;
 2 /**
 3  * 
 4  * 创建图片下载的线程
 5  * @author java
 6  *
 7  */
 8 public class TDownLoader extends Thread{
 9     private String url;
10     private String name;
11     
12     public TDownLoader(String url, String name) {
13         super();
14         this.url = url;
15         this.name = name;
16     }
17     //重写run()
18     @Override
19     public void run() {
20         WebDownLoader wd = new WebDownLoader();
21         wd.downLoader(url, name);
22     }
23     
24     public static void main(String[] args) {
25         TDownLoader td1 = new TDownLoader("https://image.baidu.com/search/detail?ct=503316480&z=0&ipn=d&word=%E5%AE%88%E7%A0%B4%E7%A6%BB&step_word=&hs=0&pn=1&spn=0&di=79296871830&pi=0&rn=1&tn=baiduimagedetail&is=0%2C0&istype=0&ie=utf-8&oe=utf-8&in=&cl=2&lm=-1&st=undefined&cs=1435309020%2C3477682663&os=1841078546%2C3614953869&simid=4194686237%2C632091804&adpicid=0&lpn=0&ln=104&fr=&fmq=1536156608183_R&fm=&ic=undefined&s=undefined&se=&sme=&tab=0&width=undefined&height=undefined&face=undefined&ist=&jit=&cg=&bdtype=0&oriquery=&objurl=http%3A%2F%2Ft2.qpic.cn%2Fmblogpic%2Fee290b3b55e018eb8fac%2F2000&fromurl=ippr_z2C%24qAzdH3FAzdH3Fr_z%26e3Bp_z%26e3Bqq_z%26e3Bv54AzdH3Fs5g2ojtk5AzdH3Frw2j_z%26e3Brir%3Ft1%3Dn8bdcba9acn0cl9%26st1%3D8b989dd8mbcdalmcl8db&gsm=0&rpstart=0&rpnum=0&islist=&querylist=","spl.jpg");
26         TDownLoader td2 = new TDownLoader("https://image.baidu.com/search/detail?ct=503316480&z=0&ipn=false&word=%E6%9D%8E%E5%B0%8F%E9%BE%99&step_word=&hs=0&pn=0&spn=0&di=94581897410&pi=0&rn=1&tn=baiduimagedetail&is=0%2C0&istype=2&ie=utf-8&oe=utf-8&in=&cl=2&lm=-1&st=-1&cs=2752933258%2C795342213&os=1992076552%2C3728441564&simid=3465896125%2C219929152&adpicid=0&lpn=0&ln=3370&fr=&fmq=1536156674237_R&fm=result&ic=0&s=undefined&se=&sme=&tab=0&width=&height=&face=undefined&ist=&jit=&cg=star&bdtype=0&oriquery=&objurl=http%3A%2F%2Fimgcache.cjmx.com%2Fstar%2F201607%2F20160719231717732.jpg&fromurl=ippr_z2C%24qAzdH3FAzdH3Ffpw6_z%26e3Bv34x_z%26e3Bv54AzdH3Fda8ma0AzdH3F8abdba8_z%26e3Bfip4s&gsm=0&rpstart=0&rpnum=0&islist=&querylist=","lxl.jpg");
27         TDownLoader td3 = new TDownLoader("https://image.baidu.com/search/detail?ct=503316480&z=0&ipn=d&word=%E6%B2%B3%E5%8D%97%E7%90%86%E5%B7%A5%E5%A4%A7%E5%AD%A6&step_word=&hs=0&pn=0&spn=0&di=115015699590&pi=0&rn=1&tn=baiduimagedetail&is=0%2C0&istype=2&ie=utf-8&oe=utf-8&in=&cl=2&lm=-1&st=-1&cs=3620107849%2C3756859208&os=1374852277%2C1275983326&simid=4171483572%2C611783800&adpicid=0&lpn=0&ln=1851&fr=&fmq=1536156735988_R&fm=result&ic=0&s=undefined&se=&sme=&tab=0&width=&height=&face=undefined&ist=&jit=&cg=&bdtype=0&oriquery=&objurl=http%3A%2F%2Fimg.gaosan.com%2Fupload%2Fwebimg%2F1785.jpg&fromurl=ippr_z2C%24qAzdH3FAzdH3Fooo_z%26e3B2w5fwg_z%26e3Bv54AzdH3F2w5hw5AzdH3F88d0la_z%26e3Bip4s&gsm=0&rpstart=0&rpnum=0&islist=&querylist=","lgd.jpg");
28         
29         td1.start();
30         td2.start();
31         td3.start();
32     }
33     
34 }

 1 package com.zzp.thread;
 2 /**
 3  * 
 4  * 创建线程：方式二
 5  * 1、实现runnable接口，重写run方法
 6  * 2、启动线程+thread类+调用start方法
 7  * 推荐使用，避免单继承造成的局限性
 8  * @author java
 9  *
10  */
11 public class StartRun implements Runnable{
12     //重写run()
13     @Override
14     public void run() {
15         for(int i=0;i<10;i++){
16             System.out.println("一边学习");
17         }
18     }
19 
20     public static void main(String[] args) {
21         //创建Thread子类对象
22         //StartRun sr = new StartRun();
23         //创建Thread类对象
24         //Thread t = new Thread(sr);
25         //启动，并不是立即启动，而是等待cpu调用，至于CPU何时调用，不知道
26         //开启线程的时机很重要
27         //t.start();
28         //如果直接调用run()方法，则是普通方法调用，不是开启多线程
29         //st.run();
30         
31         //如果创建的对象只用一次
32         new Thread(new StartRun()).start();
33         
34         for(int i=0;i<10;i++){
35             System.out.println("一边听歌");
36         }
37     }
38 }

 1 package com.zzp.thread;
 2 /**
 3  * 
 4  * 创建图片下载的线程
 5  * @author java
 6  *
 7  */
 8 public class IDownLoader implements Runnable{
 9     private String url;
10     private String name;
11     
12     public IDownLoader(String url, String name) {
13         super();
14         this.url = url;
15         this.name = name;
16     }
17     //重写run()
18     @Override
19     public void run() {
20         WebDownLoader wd = new WebDownLoader();
21         wd.downLoader(url, name);
22     }
23     
24     public static void main(String[] args) {
25         IDownLoader td1 = new IDownLoader("https://image.baidu.com/search/detail?ct=503316480&z=0&ipn=d&word=%E5%AE%88%E7%A0%B4%E7%A6%BB&step_word=&hs=0&pn=1&spn=0&di=79296871830&pi=0&rn=1&tn=baiduimagedetail&is=0%2C0&istype=0&ie=utf-8&oe=utf-8&in=&cl=2&lm=-1&st=undefined&cs=1435309020%2C3477682663&os=1841078546%2C3614953869&simid=4194686237%2C632091804&adpicid=0&lpn=0&ln=104&fr=&fmq=1536156608183_R&fm=&ic=undefined&s=undefined&se=&sme=&tab=0&width=undefined&height=undefined&face=undefined&ist=&jit=&cg=&bdtype=0&oriquery=&objurl=http%3A%2F%2Ft2.qpic.cn%2Fmblogpic%2Fee290b3b55e018eb8fac%2F2000&fromurl=ippr_z2C%24qAzdH3FAzdH3Fr_z%26e3Bp_z%26e3Bqq_z%26e3Bv54AzdH3Fs5g2ojtk5AzdH3Frw2j_z%26e3Brir%3Ft1%3Dn8bdcba9acn0cl9%26st1%3D8b989dd8mbcdalmcl8db&gsm=0&rpstart=0&rpnum=0&islist=&querylist=","spl.jpg");
26         IDownLoader td2 = new IDownLoader("https://image.baidu.com/search/detail?ct=503316480&z=0&ipn=false&word=%E6%9D%8E%E5%B0%8F%E9%BE%99&step_word=&hs=0&pn=0&spn=0&di=94581897410&pi=0&rn=1&tn=baiduimagedetail&is=0%2C0&istype=2&ie=utf-8&oe=utf-8&in=&cl=2&lm=-1&st=-1&cs=2752933258%2C795342213&os=1992076552%2C3728441564&simid=3465896125%2C219929152&adpicid=0&lpn=0&ln=3370&fr=&fmq=1536156674237_R&fm=result&ic=0&s=undefined&se=&sme=&tab=0&width=&height=&face=undefined&ist=&jit=&cg=star&bdtype=0&oriquery=&objurl=http%3A%2F%2Fimgcache.cjmx.com%2Fstar%2F201607%2F20160719231717732.jpg&fromurl=ippr_z2C%24qAzdH3FAzdH3Ffpw6_z%26e3Bv34x_z%26e3Bv54AzdH3Fda8ma0AzdH3F8abdba8_z%26e3Bfip4s&gsm=0&rpstart=0&rpnum=0&islist=&querylist=","lxl.jpg");
27         IDownLoader td3 = new IDownLoader("https://image.baidu.com/search/detail?ct=503316480&z=0&ipn=d&word=%E6%B2%B3%E5%8D%97%E7%90%86%E5%B7%A5%E5%A4%A7%E5%AD%A6&step_word=&hs=0&pn=0&spn=0&di=115015699590&pi=0&rn=1&tn=baiduimagedetail&is=0%2C0&istype=2&ie=utf-8&oe=utf-8&in=&cl=2&lm=-1&st=-1&cs=3620107849%2C3756859208&os=1374852277%2C1275983326&simid=4171483572%2C611783800&adpicid=0&lpn=0&ln=1851&fr=&fmq=1536156735988_R&fm=result&ic=0&s=undefined&se=&sme=&tab=0&width=&height=&face=undefined&ist=&jit=&cg=&bdtype=0&oriquery=&objurl=http%3A%2F%2Fimg.gaosan.com%2Fupload%2Fwebimg%2F1785.jpg&fromurl=ippr_z2C%24qAzdH3FAzdH3Fooo_z%26e3B2w5fwg_z%26e3Bv54AzdH3F2w5hw5AzdH3F88d0la_z%26e3Bip4s&gsm=0&rpstart=0&rpnum=0&islist=&querylist=","lgd.jpg");
28         
29         new Thread(td1).start();
30         new Thread(td2).start();
31         new Thread(td3).start();
32     }
33     
34 }

 1 package com.zzp.thread;
 2 /**
 3  * 
 4  * 共享资源，会出现并发问题（后面要确保线程安全）
 5  * @author java
 6  *
 7  */
 8 public class Web12306 implements Runnable{
 9     private int tikectsNum = 99;
10     @Override
11     public void run() {
12         while(true){
13             if(tikectsNum < 0){
14                 break;
15             }
16             //当设置线程延迟的时候，就会出现线程不安全的情况
17             try {
18                 Thread.sleep(200);
19             } catch (InterruptedException e) {
20                 e.printStackTrace();
21             }
22             System.out.println(Thread.currentThread().getName()+"--->"+tikectsNum--);
23         }
24     }
25     public static void main(String[] args) {
26         //一份资源
27         Web12306 wb = new Web12306();
28         //多份代理
29         new Thread(wb,"码农").start();
30         new Thread(wb,"马云").start();
31         new Thread(wb,"麻黄").start();
32     }
33 }

 1 package com.zzp.thread;
 2 /**
 3  * 
 4  * 模拟龟兔赛跑
 5  * @author java
 6  *
 7  */
 8 public class Racer implements Runnable{
 9     private static String winner;
10     @Override
11     public void run() {
12         for(int i=1;i<=100;i++){
13             //兔子每走10步，休息一次
14             /*if(Thread.currentThread().getName().equals("兔子") && (i%10 == 0)){
15                 try {
16                     Thread.sleep(200);
17                 } catch (InterruptedException e) {
18                     e.printStackTrace();
19                 }
20             }*/
21             System.out.println(Thread.currentThread().getName()+"-->"+i);
22             boolean flag = gameOver(i);
23             if(flag){
24                 break;
25             }
26         }
27         
28     }
29     public boolean gameOver(int i){
30         if(winner != null){
31             return true;
32         }else{
33             if(i==100){
34                 winner = Thread.currentThread().getName();
35                 System.out.println("winner:"+winner);
36                 return true;
37             }
38         }
39         return false;
40     }
41     
42     public static void main(String[] args) {
43         Racer rc = new Racer();
44         new Thread(rc,"乌龟").start();
45         new Thread(rc,"兔子").start();
46     }
47 }

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