ͨ¹ýrequestʵÏÖÎļþÏÂÔØ

//ͨ¹ýresponseʵÏÖÎļþÏÂÔØ
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
//
public class ResponseDemo3 extends HttpServlet {

 @Override
 protected void doGet(HttpServletRequest req, HttpServletResponse response)
   throws ServletException, IOException {

  test1(response); 
 }

 private void test2(HttpServletResponse response)
   throws FileNotFoundException, IOException {
  String path=this.getServletContext().getRealPath("/download/ÐÂͼƬ.jpg");
  //C:\apache-tomcat-7.0.22\webapps\day06\download\ÐÂͼƬ.jsp
  String filename=path.substring(path.lastIndexOf("\\")+1);
  
  InputStream in=null;
  OutputStream out=null;
  //Èç¹ûÏÂÔØÎļþÊÇÖÐÎÄÎļþ，ÔòÎļþÃûÐèÒª¾­¹ýurl±àÂë
  response.setHeader("content-disposition", "attachment;filename="+URLEncoder.encode(filename,"UTF-8"));
  try {
   in=new FileInputStream(path);
   int len=0;
   byte buffer[]=new byte[1024];
   out=response.getOutputStream();
   while((len=in.read(buffer))>0){
    out.write(buffer,0,len);
   }
  }finally{
   if(in!=null){
    try{
     
     in.close();
    }catch(Exception e){
     e.printStackTrace();
    }    
   }
  }
 }
 private void test1(HttpServletResponse response)
 throws FileNotFoundException, IOException {
  String path=this.getServletContext().getRealPath("/download/new.jpg");
  //C:\apache-tomcat-7.0.22\webapps\day06\download\new.jsp
  String filename=path.substring(path.lastIndexOf("\\")+1);
  
  InputStream in=null;
  OutputStream out=null;
  response.setHeader("content-disposition", "attachment;filename="+filename);
  

  try {
   in=new FileInputStream(path);
   int len=0;
   byte buffer[]=new byte[1024];
   out=response.getOutputStream();
   while((len=in.read(buffer))>0){
    out.write(buffer,0,len);
   }
  }finally{
   if(in!=null){
    try{
     
     in.close();
    }catch(Exception e){
     e.printStackTrace();
    }    
   }
  }
 }
}