原生servlet配合smartupload实现批量下载和批量上传

废话不多说,直接贴代吗

页面代码:

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>


<html>
  <head>
    <base href="<%=basePath%>">

    <title>My JSP 'index.jsp' starting pagetitle>

    <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">
    

  head>

  <body>
  ${msg }
  上传
  <form action="<%=basePath %>/SmartServlet" method="post" enctype="multipart/form-data">
  <input type="file" name="file1">
    <input type="file" name="file2">
      <input type="file" name="file3">
        <input type="file" name="file4">
  <input type="submit" value="上传">
  form>

  <hr/>
  批量下载
   <form action="<%=basePath%>/SmartDownServlet" method="get">
        <input type="checkbox"  name="filename" value="img1.jpg">Image2
        <input type="checkbox"  name="filename" value="img2.jpg">Image3
        <input type="checkbox"  name="filename" value="img3.jpg">Image4
        <input type="submit" value="下载">
     form> 
  body>
html>

批量上传,servlet代码,需要注意的是需要将表单设置为enctype=”multipart/form-data”,这样就会以二进制流的形式传输表单

package com.leige.servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.jspsmart.upload.SmartUpload;

public class SmartServlet 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 {
        String path=this.getServletContext().getRealPath("/img");
        System.out.println(path);
        SmartUpload smartUpload=new SmartUpload();
        //初始化对象
        smartUpload.initialize(getServletConfig(), request, response);
                //设置上传文件大小
        smartUpload.setMaxFileSize(1024*1024*10);
                //设置所有文件的大小
        smartUpload.setTotalMaxFileSize(1024*1024*100);
                //设置允许上传文件类型
        smartUpload.setAllowedFilesList("txt,jpg,gif,png");
                String result = "上传成功!";

                    try {
                        //设置禁止上传的文件类型
                        smartUpload.setDeniedFilesList("rar,jsp,js");
                        //上传文件
                        smartUpload.upload();
                        int count = smartUpload.save(path);
                        System.out.println("上传成功" +  count + "个文件!");
                    } catch (Exception e) {
                    //smartupload定义的一些错误代码,挑出常用的
                        result = "上传失败!";
                        if(e.getMessage().indexOf("1015") != -1){
                            result = "上传失败:上传文件类型不正确!";
                        }else if (e.getMessage().indexOf("1010") != -1){
                            result = "上传失败:上传文件类型不正确!";
                        }else if (e.getMessage().indexOf("1105") != -1){
                            result = "上传失败:上传文件大小大于允许上传的最大值!";
                        }else if (e.getMessage().indexOf("1110") != -1){
                            result = "上传失败:上传文件总大小大于允许上传总大小的最大值!";
                        }
                        e.printStackTrace();
                    } 
                request.setAttribute("msg", result);
                request.getRequestDispatcher("/index.jsp").forward(request, response);

    }

}

批量下载,需要注意的是,当用户选择批量下载时,我们不可能每个文件都弹出一个下载框,这样在体验上也不好,而且大量数据不经过压缩,就传输,也是对带宽的浪费,所以好的解决办法,压缩成包:

package com.leige.servlet;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.io.IOUtils;

import com.jspsmart.upload.Files;
import com.jspsmart.upload.SmartUpload;
import com.jspsmart.upload.SmartUploadException;

public class SmartDownServlet 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 {

        //设置请求头信息
        response.setContentType("application/x-msdownload");
        response.setHeader("Content-Disposition", "attachment;filename=test.zip");
        String path = getServletContext().getRealPath("/") + "img/";
        //初始化smartupload
        SmartUpload sm=new SmartUpload();
        sm.initialize(getServletConfig(), request, response);
        sm.setContentDisposition(null);
        String[] fileNames=request.getParameterValues("filename");
        String str = "";
        String rt = "\r\n";
        //返回一个压缩包
        ZipOutputStream zos = new ZipOutputStream(response.getOutputStream());
        for(String filename : fileNames){
            str += filename + rt;
            File file = new File(path + filename);
            zos.putNextEntry(new ZipEntry(filename));
            FileInputStream fis = new FileInputStream(file);
            //复制文件到压缩流中
            IOUtils.copy(fis, zos);     
            zos.flush();
            fis.close();
        }
        //设置注释
        zos.setComment("下载成功:" + rt + str);
        zos.flush();
        zos.close();
    }

}

下载和上传使用非常广泛,希望大家能掌握住

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