servlet 3.0 文件上传下载

1.需求场景

利用servlet3.0 实现文件上传

2.项目环境

servlet  jsp  javabean

3.功能实现

package com.demo.action;import java.io.File;import java.io.IOException;import java.util.List;import javax.servlet.ServletException;import javax.servlet.annotation.MultipartConfig;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.Part;@WebServlet("/uploadServlet")@MultipartConfigpublic class UploadServlet extends HttpServlet {private static final long serialVersionUID = 1L;@Overrideprotected void service(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException {request.setCharacterEncoding("UTF-8");response.setContentType("text/html;charset=UTF-8");String status="success";String fileName="demo";request.setCharacterEncoding("utf-8");response.setCharacterEncoding("utf-8");response.setContentType("text/html;charset=utf-8");// 存储路径String savePath = request.getServletContext().getRealPath("uploadfile");    // 上传单个文件// Servlet3.0将multipart/form-data的POST请求封装成Part，通过Part对上传的文件进行操作。Part part = request.getPart("file");// 通过表单file控件(<input type="file" name="file">)的名字直接获取Part对象// Servlet3没有提供直接获取文件名的方法,需要从请求头中解析出来// 获取请求头，请求头的格式：form-data; name="file"; filename="demo.zip"String header = part.getHeader("content-disposition");// 获取文件名String fileName = getFileName(header);String filePath = savePath + File.separator + fileName;String newFileName = File.separator+System.currentTimeMillis()+".zip";//写成zip后缀，能够在window环境，浏览器下直接下载String resultFielPath=savePath+newFileName;String downloadpath="uploadfile"+newFileName;// 把文件写到指定路径part.write(filePath);List<String> strlist = FileUtil.readFile(filePath);if(strlist!=null && imeilist.size()>0){for (int i = 0; i < strlist.size(); i++) {       //文件写入FileUtil.writeFile(strlist.get(i)+"\t"+result+"\n", resultFielPath);}}request.setAttribute("downloadpath",downloadpath); //文件下载路径request.setAttribute("message", "上传解析成功");request.setAttribute("status", status);    request.getRequestDispatcher("index.jsp").forward(request,response);}/** * 根据请求头解析出文件名 * @param header 请求头 * @return 文件名 */public String getFileName(String header) {String[] tempArr1 = header.split(";");String[] tempArr2 = tempArr1[2].split("=");// 获取文件名，兼容各种浏览器String fileName = tempArr2[1].substring(tempArr2[1].lastIndexOf("\\") + 1).replaceAll("\"", "");return fileName;}}