一个简单的http服务器(Java)

测试方法:

运行后打开IE,输入http://localhost/xxx.htm,其中xxx.htm是你放在e:\webroot\中的同名文件,

例如,在e:\webroot\目录下有clotho.htm,可以访问http://localhost/clotho.htm来浏览.

另外,如果程序不是使用默认的80端口,可以在localhost后面加端口号,

例如,代码改成HttpServer.port = 8086,可以访问http://localhost:8086/clotho.htm来浏览.

 

代码

import  java.io.BufferedInputStream;
import  java.io.BufferedOutputStream;
import  java.io.BufferedReader;
import  java.io.FileInputStream;
import  java.io.InputStream;
import  java.io.InputStreamReader;
import  java.io.OutputStream;
import  java.net.Socket;
import  java.net.ServerSocket;
import  java.util.Date;

public   class  HttpServer  implements  Runnable {
     public   static   void  main(String args[]) {
        HttpServer.root  =   " e:\\webroot\\ " ;  //  服务器根目录
        HttpServer.port  =   80 ;  //  浏览器默认请求80端口
        HttpServer.listen();
    }

     public   static   void  listen() {
        ServerSocket serverSocket  =   null ;
         try  {
            serverSocket  =   new  ServerSocket(port);
             while  ( true ) {
                Socket socket  =  serverSocket.accept();
                HttpServer server  =   new  HttpServer(socket);
                Thread thread  =   new  Thread(server);
                thread.start();
            }
        }  catch  (Exception ex) {
            ex.printStackTrace();
        }  finally  {
             try  {

            }  catch  (Exception ex) {
                ex.printStackTrace();
            }
        }
    }

     /**
     * 服务器根目录
      */
     public   static  String root;

     /**
     * 端口
      */
     public   static   int  port;

     /**
     * 单个请求的套接字
      */
     private  Socket socket;

     public  HttpServer(Socket socket) {
         this .socket  =  socket;
    }

     public   void  run() {
         try  {
             //  获取请求信息
            InputStream is  =  socket.getInputStream();
            InputStreamReader isr  =   new  InputStreamReader(is);
            BufferedReader br  =   new  BufferedReader(isr);

             //  生成响应数据
            String filename  =  getRequestFilename(br);
            String contentType  =  getContentType(filename);
            FileInputStream fis  =   new  FileInputStream(root  +  filename);
            BufferedInputStream bis  =   new  BufferedInputStream(fis);
             int  length  =  bis.available();
            String respText  =  getResponseText(length, contentType);

             //  响应请求的浏览器
            OutputStream os  =  socket.getOutputStream();
            BufferedOutputStream bos  =   new  BufferedOutputStream(os);
            bos.write(respText.getBytes());  //  返回http header信息

             byte  buffer[]  =   new   byte [length];
            bis.read(buffer,  0 , length);
            bos.write(buffer);  //  返回文件数据
            bos.flush();
            bos.close();

            br.close();
        }  catch  (Exception ex) {
            ex.printStackTrace();
        }  finally  {
             try  {
                socket.close();
            }  catch  (Exception e) {
                e.printStackTrace();
            }
        }
    }

     /**
     * 解析请求的页面文件名
      */
     private  String getRequestFilename(BufferedReader br) {
        String filename  =   null ;
        String line  =   null ;
         try  {
             while  ((line  =  br.readLine())  !=   null ) {
                 if  (line.startsWith( " GET " )) {
                    String[] segments  =  line.split( "   " );
                    filename  =  segments[ 1 ];
                }
                 if  (line.length()  ==   0   ||  line.equals( " \n " )) {
                     break ;
                }
            }
        }  catch  (Exception ex) {
            ex.printStackTrace();
        }
         return  filename;
    }

     /**
     * ContentType属性指定响应的http内容类型
      */
     private  String getContentType(String filename) {
         int  pos  =  filename.lastIndexOf( ' . ' );
        String ext  =  filename.substring(pos  +   1 ).toLowerCase();
        String contentType  =   null ;
         switch  (ext.charAt( 0 )) {
         case   ' h ' :  //  htm html
            contentType  =   " text/html " ;
         case   ' j ' :  //  jpg
            contentType  =   " image/jpg " ;
         case   ' g ' :  //  gif
            contentType  =   " image/gif " ;
         default :
            contentType  =   " */ "   +  ext;
        }
         return  contentType;
    }

     /**
     * 生成响应的http header信息
      */
     private  String getResponseText( int  length, String contentType) {
        StringBuilder sb  =   new  StringBuilder();
        sb.append( " HTTP/1.1 200 OK\n " );
        sb.append( " Date:  "   +   new  Date()  +   " \n " );
        sb.append( " Server: Clotho\n " );
        sb.append( " Accept-Ranges: bytes\n " );
        sb.append( " Content-Length:  "   +  length  +   " \n " );
        sb.append( " Keep-Alive: true\n " );
        sb.append( " Connection: Keep-Alive\n " );
        sb.append( " Content-Type:  "   +  contentType  +   " \n " );
        sb.append( " \n " );
         return  sb.toString();
    }
}