标签：java web tomcat servlet 文件下载
需求：实现一个具有文件下载功能的网页，主要下载压缩包和图片
两种实现方法：
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Insert title here</title> </head> <body> <h1>通过链接下载文件</h1> <a href="/day06/download/cors.zip">压缩包</a> <a href="/day06/download/1.png">图片</a> </body> </html>
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Insert title here</title> </head> <body> <h1>通过链接下载文件</h1> <a href="/day06/download/cors.zip">压缩包</a> <a href="/day06/download/1.png">图片</a> <h1>通过servlet程序下载文件</h1> <a href="/day06/ServletDownload?filename=cors.zip">压缩包</a> <a href="/day06/ServletDownload?filename=1.png">图片</a> </body> </html>
package com.lsgjzhuwei.servlet.response;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class ServletDownload
*/
@WebServlet(asyncSupported = true, urlPatterns = { "/ServletDownload" })
public class ServletDownload extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public ServletDownload() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//获得请求文件名
String filename = request.getParameter("filename");
System.out.println(filename);
//设置文件MIME类型
response.setContentType(getServletContext().getMimeType(filename));
//设置Content-Disposition
response.setHeader("Content-Disposition", "attachment;filename="+filename);
//读取目标文件，通过response将目标文件写到客户端
//获取目标文件的绝对路径
String fullFileName = getServletContext().getRealPath("/download/" + filename);
//System.out.println(fullFileName);
//读取文件
InputStream in = new FileInputStream(fullFileName);
OutputStream out = response.getOutputStream();
//写文件
int b;
while((b=in.read())!= -1)
{
out.write(b);
}
in.close();
out.close();
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
}
标签：java web tomcat servlet 文件下载
原文地址：http://blog.csdn.net/longshengguoji/article/details/39433307
