深入浅出的Java网络通信

逃离我推掉我的手 2021-09-15 00:02 380阅读 0赞

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**代码展示**

package two;
    
    import java.io.BufferedReader;
    import java.io.InputStreamReader;
    import java.net.URL;
    
    public class Three {
    
     public static void main(String[] args) {
       // TODO Auto-generated method stub
    
       try {
         URL url = new URL("http://www.baidu.com");
         System.out.println(url.getProtocol());
         System.out.println(url.getHost());
         System.out.println(url.getPort());
         System.out.println(url.getFile());
         
         BufferedReader br = new BufferedReader(new InputStreamReader(url.openStream()));
         String s;
         while((s=br.readLine())!=null){
           System.out.println(s);
         }
         br.close();
         
       }
       catch(Exception e) {
         System.out.println(e);
       }
     }
    }

输出结果：

http
    www.baidu.com
    -1
    
    <!DOCTYPE html>
    
    <html> <head><meta http-equiv=content-type content=text/html;charset=utf-8><meta http-equiv=X-UA-Compatible content=IE=Edge><meta content=always name=referrer><link rel=stylesheet type=text/css href=http://s1.bdstatic.com/r/www/cache/bdorz/baidu.min.css><title>鐧惧害涓?涓嬶紝浣犲氨鐭ラ亾</title></head>
    <body link=#0000cc> <div id=wrapper> <div id=head> <div class=head_wrapper> <div class=s_form> 
    <div class=s_form_wrapper> <div id=lg> 
    <img hidefocus=true src=//www.baidu.com/img/bd_logo1.png width=270 height=129> </div> 
    <form id=form name=f action=//www.baidu.com/s class=fm> <input type=hidden name=bdorz_come value=1> <input type=hidden name=ie value=utf-8> 
    <input type=hidden name=f value=8> <input type=hidden name=rsv_bp value=1> 
    <input type=hidden name=rsv_idx value=1> <input type=hidden name=tn value=baidu>
    <span class="bg s_ipt_wr"><input id=kw name=wd class=s_ipt value maxlength=255 autocomplete=off autofocus></span><span class="bg s_btn_wr">
    <input type=submit id=su value=鐧惧害涓?涓? class="bg s_btn"></span> </form> </div> </div> 
    <div id=u1> <a href=http://news.baidu.com name=tj_trnews class=mnav>鏂伴椈</a> 
    <a href=http://www.hao123.com name=tj_trhao123 class=mnav>hao123</a> <a href=http://map.baidu.com name=tj_trmap class=mnav>鍦板浘</a> <a href=http://v.baidu.com name=tj_trvideo class=mnav>瑙嗛</a> 
    <a href=http://tieba.baidu.com name=tj_trtieba class=mnav>璐村惂</a> <noscript> <a href=http://www.baidu.com/bdorz/login.gif?login&tpl=mn&u=http%3A%2F%2Fwww.baidu.com%2f%3fbdorz_come%3d1 name=tj_login class=lb>鐧诲綍</a> </noscript> 
    <script>document.write('<a href="http://www.baidu.com/bdorz/login.gif?login&tpl=mn&u='+ encodeURIComponent(window.location.href+ (window.location.search === "" ? "?" : "&")+ "bdorz_come=1")+ '" name="tj_login" class="lb">鐧诲綍</a>');</script> <a href=//www.baidu.com/more/ name=tj_briicon class=bri style="display: block;">鏇村浜у搧</a> </div> </div> </div> <div id=ftCon>
    <div id=ftConw> <p id=lh> 
    <a href=http://home.baidu.com>鍏充簬鐧惧害</a> 
    <a href=http://ir.baidu.com>About Baidu</a> </p> 
    <p id=cp>©2017 Baidu 
    <a href=http://www.baidu.com/duty/>浣跨敤鐧惧害鍓嶅繀璇?</a>  <a href=http://jianyi.baidu.com/ class=cp-feedback>鎰忚鍙嶉</a> 浜琁CP璇?030173鍙?  <img src=//www.baidu.com/img/gs.gif> </p> </div> </div> </div> </body> </html>

public String getProtocol():获取URL的协议名。

public String getHost():获取URL的主机名。

public int getPort():获取URL的端口号。

Public String getFiel():获取该URL的文件名。

public String getQuery():获取该URL的路径。

public String getPath():获取该URL的路径。

//创建一个对象
    URL url = new URL("http:///www.baidu.com/");
    //URL对象的openStream()方法返回一个InputStream
    InputStream is = url.openStream();
    
    InputStreamReader isr = new InputStreamReader(is);
    BufferedReader br = new BufferedReader(isr);

可以简化

BufferedReader br = new BufferedReader(new InputStreamReader(url.openStream()));

读取内容

String str;
    while((str=br.readLine()) != null){
    System.out.println(str);
    }

![2018031016491822][]

在new module 中选择java library，配置好就可以建立个文件编写代码，然后进行运行了。

#####    总结 #####

URL url = new URL("http://www.baidu.com");
    
    url.getProtocol()--->http
    url.getHost()--->www.baidu.com
    
    URL url = new URL("http://www.baidu.com");
    BufferedReader br = new BufferedReader(new InputStreamReader(url.openStream()));
    
    String str;
    while((str = br.readLine()) != null){
    System.out.println(str);
    }
    
    br.close();

[2018031016491822]: /images/20210724/cabe10246a254b7688c65d6bb9c314d1.png