Jsp+Servlet实现文件上传下载删除上传文件（三）

作者：袖梨 2025-07-03

这篇文章主要为大家详细介绍了Jsp+Servlet实现文件上传下载功能的第三部分删除上传文件，具有一定的参考价值，感兴趣的小伙伴们可以参考一下

接着上一篇讲：Jsp+Servlet实现文件上传下载（二）--文件列表展示

本章来实现一下删除已上传文件，同时优化了一下第一章中的代码。

废话少说，上代码得意

1.调整列表页面list.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <html> <head><title>上传文件列表</title> </head> <body><h3>文件列表</h3> <table class="acclist_tab" border="1" bordercolor="#000000" cellspacing="0" cellpadding="2" style="border-collapse:collapse;"><tr> <th>文件名</th> <th>文件大小（KB）</th> <th>操作</th></tr><c:if test="${not empty accessoryList}"> <c:forEach items="${accessoryList}" var="acc"><tr> <td>${acc.fileName}</td> <td>${acc.fileSize}</td> <td><a href="<%=request.getContextPath()%>/removeUploadedFile?id=${acc.id}" rel="external nofollow" >删除</a></td></tr> </c:forEach></c:if> </table> </body> </html>

2.新增FileUtils工具类

package util;import java.io.File;/*** 文件操作工具类** @author xusucheng* @create 2017-12-30**/ public class FileUtils {public static boolean delete(String path){ File file = new File(path); if(!file.isFile()){System.out.println("删除失败，文件："+path+"不存在！");return false; }file.delete();return true;} }

3.调整附件实体DAO，新增load方法

package dao.upload;import entity.upload.EntityAccessory; import util.DBUtil;import java.math.BigDecimal; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List;/*** 附件上传DAO** @author xusucheng* @create 2017-12-29**/ public class AccessoryDao {public static void add(EntityAccessory entity) { Connection conn = DBUtil.getConnection(); String sql = "insert into tbl_accessory(file_name,file_size,file_ext_name,file_path) values(?,?,?,?)"; try {PreparedStatement ps = conn.prepareStatement(sql);ps.setString(1, entity.getFileName());ps.setDouble(2, entity.getFileSize());ps.setString(3, entity.getFile_ext_name());ps.setString(4, entity.getFilePath());ps.execute();//conn.commit(); DBUtil.close(null, ps, conn); } catch (SQLException e) {e.printStackTrace(); }} public static List<EntityAccessory> list() { Connection conn = DBUtil.getConnection(); String sql = "select id,file_name,file_size,file_ext_name,file_path from tbl_accessory"; List<EntityAccessory> accessoryList = new ArrayList<>(); try {PreparedStatement ps = conn.prepareStatement(sql);ResultSet rs = ps.executeQuery(); while (rs.next()) { EntityAccessory entity = new EntityAccessory(); entity.setId(rs.getInt("id")); entity.setFileName(rs.getString("file_name")); entity.setFileSize(new BigDecimal(rs.getDouble("file_size") / 1024).setScale(2, BigDecimal.ROUND_HALF_UP).doubleValue()); entity.setFile_ext_name(rs.getString("file_ext_name")); entity.setFilePath(rs.getString("file_path")); accessoryList.add(entity);} DBUtil.close(rs, ps, conn); } catch (SQLException e) {e.printStackTrace(); }return accessoryList; } public static EntityAccessory load(int id){ Connection conn = DBUtil.getConnection(); PreparedStatement ps=null; ResultSet rs=null; EntityAccessory entity = new EntityAccessory(); String sql = "select id, file_name,file_size,file_ext_name,file_path from tbl_accessory where id=?"; try {ps = conn.prepareStatement(sql);ps.setInt(1,id);rs = ps.executeQuery();while (rs.next()){ entity.setId(rs.getInt("id")); entity.setFileName(rs.getString("file_name")); entity.setFileSize(rs.getDouble("file_size")); entity.setFile_ext_name(rs.getString("file_ext_name")); entity.setFilePath(rs.getString("file_path"));} } catch (SQLException e) {e.printStackTrace(); }finally {DBUtil.close(rs,ps,conn); }return entity;} public static void remove(int id) { Connection conn = DBUtil.getConnection(); String sql = "delete from tbl_accessory where id=?"; try {PreparedStatement ps = conn.prepareStatement(sql);ps.setInt(1,id);ps.execute();//conn.commit(); mysql默认开启了autocommit DBUtil.close(null,ps,conn); } catch (SQLException e) {e.printStackTrace(); }} }

4.新增删除文件处理器，removeUploadedFileServlet

package servlet.upload;import dao.upload.AccessoryDao; import entity.upload.EntityAccessory; import util.FileUtils;import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException;/*** 删除已上传文件** @author xusucheng* @create 2017-12-30**/ @WebServlet("/removeUploadedFile") public class removeUploadedFileServlet extends HttpServlet {@Overrideprotected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //String filePath = request.getParameter("filePath"); int fileId = Integer.valueOf(request.getParameter("id")); EntityAccessory entity = AccessoryDao.load(fileId); //删除文件 FileUtils.delete(entity.getFilePath()); //删除数据库记录 AccessoryDao.remove(fileId);//跳回到文件列表页 //request.getRequestDispatcher("listUploadedFiles").forward(request, response); response.sendRedirect("listUploadedFiles");} @Overrideprotected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response);} }

5.测试效果截图

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