使用commos-fileupload实现文件上传与下载

来源：互联网发布：软件项目经理jd 编辑：程序博客网时间：2024/06/05 08:58

一文件的上传

实体类

import java.sql.Timestamp;/** *  * @Decription 文件上传实体类 * @author 刘楠 *  * @time2016-1-31上午11:17:46 */public class Upfile {private String id;// ID主键 使用uuid随机生成private String uuidname; // UUID名称private String filename;//文件名称private String savepath; // 保存路径private Timestamp uploadtime; // 上传时间private String description;// 文件描述private String username; // 用户名public Upfile() {super();}public Upfile(String id, String uuidname, String filename, String savepath,Timestamp uploadtime, String description, String username) {super();this.id = id;this.uuidname = uuidname;this.filename = filename;this.savepath = savepath;this.uploadtime = uploadtime;this.description = description;this.username = username;}public String getDescription() {return description;}public String getFilename() {return filename;}public String getId() {return id;}public String getSavepath() {return savepath;}public Timestamp getUploadtime() {return uploadtime;}public String getUsername() {return username;}public String getUuidname() {return uuidname;}public void setDescription(String description) {this.description = description;}public void setFilename(String filename) {this.filename = filename;}public void setId(String id) {this.id = id;}public void setSavepath(String savepath) {this.savepath = savepath;}public void setUploadtime(Timestamp uploadtime) {this.uploadtime = uploadtime;}public void setUsername(String username) {this.username = username;}public void setUuidname(String uuidname) {this.uuidname = uuidname;}}

页面

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html>  <head>    <base href="<%=basePath%>">        <title>My JSP 'upload.jsp' starting page</title>    <meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0">    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"><!--<link rel="stylesheet" type="text/css" href="styles.css">-->  </head>    <body>    <h1>文件上传</h1>    <form action="${pageContext.request.contextPath }/upload" method="post" enctype="multipart/form-data">   <table>   <tr>   <td> 上传用户名:</td>   <td><input type="text" name="username"/></td>   </tr>   <tr>   <td> 上传文件:</td>   <td><input type="file" name="file"/></td>   </tr>   <tr>   <td> 描述:</td>   <td><textarea rows="5" cols="50" name="description"></textarea></td>   </tr>    <tr>   <td><input type="submit" value="上传开始"/></td>   </tr>   </table>    </form>    <div>${msg }</div>    <a href="${pageContext.request.contextPath  }/index.jsp">返回主页</a>  </body></html>

Servlet

import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.apache.commons.fileupload.FileUploadBase.FileSizeLimitExceededException;import org.apache.commons.fileupload.FileUploadBase.SizeLimitExceededException;import org.apache.commons.fileupload.servlet.ServletFileUpload;import com.itheima.domain.Upfile;import com.itheima.exception.MyException;import com.itheima.service.UpfileService;import com.itheima.service.impl.UpfileServiceImpl;import com.itheima.untils.WebUntil;public class UploadFileServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doPost(request, response);}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {//判断表单是不是多个部分组成的if(!ServletFileUpload.isMultipartContent(request)){request.setAttribute("msg", "表单个设置错误,请检查enctype属性是是否设置正确");request.getRequestDispatcher("/upload.jsp").forward(request, response);return ;}//是多部分组成的就获取并遍历返回一个文件上传对象,包含上传的所有信息try {Upfile upfile=WebUntil.upload(request);UpfileService upfileService=new UpfileServiceImpl();boolean flag=upfileService.add(upfile);if(flag){request.setAttribute("msg", "上传成功");request.getRequestDispatcher("/upload.jsp").forward(request, response);return ;}else{request.setAttribute("msg", "上传失败,请重试");request.getRequestDispatcher("/upload.jsp").forward(request, response);return ;}}catch (FileSizeLimitExceededException e) {e.printStackTrace();request.setAttribute("msg", "单个文件大小 ,超过最大限制");request.getRequestDispatcher("/upload.jsp").forward(request, response);return ;} catch (SizeLimitExceededException e) {e.printStackTrace();request.setAttribute("msg", "总文件大小 ,超过最大限制");request.getRequestDispatcher("/upload.jsp").forward(request, response);return ;}}}

工具类

import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.io.UnsupportedEncodingException;import java.util.ArrayList;import java.util.List;import java.util.UUID;import javax.servlet.http.HttpServletRequest;import org.apache.commons.fileupload.FileItem;import org.apache.commons.fileupload.FileUploadBase;import org.apache.commons.fileupload.FileUploadBase.FileSizeLimitExceededException;import org.apache.commons.fileupload.FileUploadBase.SizeLimitExceededException;import org.apache.commons.fileupload.FileUploadException;import org.apache.commons.fileupload.ProgressListener;import org.apache.commons.fileupload.disk.DiskFileItemFactory;import org.apache.commons.fileupload.servlet.ServletFileUpload;import com.itheima.domain.Upfile;import com.itheima.exception.MyException;/** * 文件上传工具类* @Decription TODO * @author 刘楠 * * @time2016-1-31下午12:56:02 */public class WebUntil {/** * 文件上传的方法 * @param request  请求参数传入 * @return  返回一个Upfile对象 * @throws FileSizeLimitExceededException  * @throws SizeLimitExceededException  * @throws IOException  */public static Upfile upload(HttpServletRequest request) throws FileSizeLimitExceededException, SizeLimitExceededException {Upfile upfile=new Upfile();ArrayList<String> fileList=initList();try {//获取磁盘文件对象工厂DiskFileItemFactory factory=new DiskFileItemFactory();String tmp=request.getSession().getServletContext().getRealPath("/tmp");System.out.println(tmp);//初始化工厂setFactory(factory,tmp);//获取文件上传解析器ServletFileUpload upload=new ServletFileUpload(factory);//初始化解析器setUpload(upload);//获取文件列表集合List<FileItem> list = upload.parseRequest(request);//遍历for (FileItem items : list) {//判断 是不是普通表单个对象if(items.isFormField()){//获取上传表单的nameString fieldName=items.getFieldName();//valueString fieldValue=items.getString("UTF-8");//判断if("username".equals(fieldName)){//设置upfile.setUsername(fieldValue);}else if("description".equals(fieldName)){//设置属性upfile.setDescription(fieldValue);}}else{//是文件就准备上传//获取文件名String filename=items.getName();//处理因为浏览器不同而导致的 获得 的  文件名的 差异int index=filename.lastIndexOf("\\");if(index!=-1){filename=filename.substring(index+1);}//生成随机的文件名String uuidname=generateFilename(filename);//获取上传的文件路径String savepath=request.getSession().getServletContext().getRealPath("/WEB-INF/upload");//获取请求对象中的输入流InputStream in = items.getInputStream();//将文件打散存放在不同的路径,求出路径savepath=generateRandomDir(savepath,uuidname);//复制文件uploadFile(in,savepath,uuidname);String id=UUID.randomUUID().toString();upfile.setId(id);upfile.setSavepath(savepath);upfile.setUuidname(uuidname);upfile.setFilename(filename);//清除缓存items.delete();}}}catch ( FileUploadBase.FileSizeLimitExceededException e) {//抛出出异常throw e;} catch (FileUploadBase.SizeLimitExceededException e) {//抛出出异常throw e;}catch (FileUploadException e) {e.printStackTrace();} catch (UnsupportedEncodingException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} catch (Exception e) {e.printStackTrace();}return upfile;}/** * 初始化文件列表 * @return */private static ArrayList<String> initList() { ArrayList<String>   list=new ArrayList<String>();   list.add(".jpg");   list.add(".rar");   list.add(".txt");   list.add(".png");         return  list;}/** * 复制文件 * @param in items中的输入流 * @param savepath 保存路径 * @param uuidname 文件名 */private static void uploadFile(InputStream in, String savepath,String uuidname) {//获取文件File file=new File(savepath, uuidname);OutputStream out = null;try {int len=0;byte [] buf=new byte[1024];//获取输出流out = new FileOutputStream(file);while((len=in.read(buf))!=-1){out.write(buf, 0, len);}} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}finally{try {in.close();} catch (IOException e) {e.printStackTrace();}try {out.close();} catch (IOException e) {e.printStackTrace();}}}/** * 生成随机的存放路径 * @param savepath 保存路径 * @param uuidname  生成的uuid名称 * @return * 使用hashcode完成 */private static String generateRandomDir(String savepath, String uuidname) {//转化为hashcodeSystem.out.println("上传路径"+savepath);System.out.println("UUIDNAME"+uuidname);int hashcode=uuidname.hashCode();//容器StringBuilder sb=new StringBuilder();while(hashcode>0){//与上15int tmp=hashcode&0xf;sb.append("/");sb.append(tmp+"");hashcode=hashcode>>4;}//拼接新的路径String path=savepath+sb.toString();System.out.println("path"+path);File file=new File(path);//判断路径存不存在if(!file.exists()){//不存在就创建file.mkdirs();}//返回保存路径 return path;}/** * 生成新的文件名 * @param uuidname 随机的ID名字 * @param filename 原来的名 * @return */private static String generateFilename( String filename) {String uuidname=UUID.randomUUID().toString();return uuidname.replace("-", "").toString()+"_"+filename;}/** * 初始化解析器 * @param upload */private static void setUpload(ServletFileUpload upload) {// 设置 字符编码upload.setHeaderEncoding("utf-8");//设置文件大小upload.setFileSizeMax(1024*1024*20);//设置总文件大小upload.setSizeMax(1024*1024*50);//设置进度监听器upload.setProgressListener(new ProgressListener() {public void update(long pBytesRead, long pContentLength, int pItems) {System.out.println("已经读取:  "+pBytesRead+",总共有: "+pContentLength+", 第"+pItems+"个");}}); }/** * 工厂初始化方法 * @param factory * @param tmp  缓冲目录 */private static void setFactory(DiskFileItemFactory factory, String tmp) {/// 配置初始化值缓冲区factory.setSizeThreshold(1024*1024);File file=new File(tmp);//设置缓冲目录factory.setRepository(file);}}

二文件下载

Servlet

public class DownupfileServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doPost(request, response);}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {//获取IDString id=request.getParameter("id");//业务层的接口UpfileService upfileService=new UpfileServiceImpl();//根据ID查找这个对象Upfile upfile=upfileService.findUpfileById(id);if(upfile==null){return;}//获取文件的真实名称String filename=upfile.getFilename();//如果文件名中有中文,需要转码,不然就下载时没有文件名filename=URLEncoder.encode(filename, "utf-8");//更改过的名称String uuidname=upfile.getUuidname();//保存路径String savepath=upfile.getSavepath();File file=new File(savepath,uuidname);//判断文件 是否存在if(!file.exists()){request.setAttribute("msg", "下载 的文件过期了");request.getRequestDispatcher("/index").forward(request, response);return;}//设置文件下载响应头信息response.setHeader("Content-disposition", "attachement;filename="+filename);//使用IO流输出InputStream in = new FileInputStream(file);ServletOutputStream out = response.getOutputStream();int len=0;byte [] buf=new byte[1024];while((len=in.read(buf))!=-1){out.write(buf, 0, len);}in.close();}}

数据库

create database upload_download_exercise;use upload_download_exercise;create table upfiles(   id varchar(100), //使用UUID生成   uuidname varchar(255),//uuid加上原来的文件名   filename varchar(100),//真实文件名   savepath varchar(255),//保存路径   uploadtime timestamp,//上传时间   description varchar(255),//描述   username varchar(10) 上传人);

0 0