下载

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


public class MyServletDemo4 extends HttpServlet {

        public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
                // 获取文件的真实路径
                String filePath = getServletContext().getRealPath("/1.jpg");
                
                // 通知客户端以下载的方式打开
                response.setHeader("Content-Disposition", "attachment;filename=1.jpg");
                // 通知客户端正文的MIME类型  图片的类型为： application-octet-stream
                response.setHeader("Content-Type","application-octet-stream");
                
                InputStream in = new FileInputStream(filePath);
                OutputStream out = response.getOutputStream();
                int len = 0;
                byte[] b = new byte[1024];
                while((len = in.read(b))!= -1){
                  out.write(b,0,len);
                }
                in.close();
                out.close();
        }


        public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
                doGet(request, response);
        }


}