最近的项目开发中,遇到了一个多文件上传的问题,即在不刷新页面的情况下,上传多个文件至服务器。现总结分享如下:

本文主要采用了基于jsp的ajax,jquery,servlet等技术。

1.upload.jsp

点击上传时,调用对应的fileupload函数,通过ajax将文件异步传送到servlet中处理。注意在文件上载时,所使用的编码类型应当是“multipart/form-data”,它既可以发送文本数据,也支持二进制数据上载。

<%@ page language="java" contentType="text/html; charset=utf-8" 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" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<base href="<%=basePath%>">
<title>Insert title here</title>
<script type="text/javascript" src="/UploadFiles/2021-04-02/jquery.js">

2.PictureServlet.java

通过该servlet接受jsp上传的数据流,存储到相应路径,并解析出文件名。

package com.servlet;
import java.io.BufferedOutputStream;
import java.io.DataOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.ServletInputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.realty.base.action.BuildingAction;
/**
 * Servlet implementation class PictureServlet
 */
@WebServlet("/PictureServlet")
public class PictureServlet extends HttpServlet {
  private static final long serialVersionUID = 1L;
                                                    
  /**
   * @see HttpServlet#HttpServlet()
   */
  public PictureServlet() {
    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
    doPost(request,response);
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
     response.setContentType("text/xml");//是xml
      response.setHeader("Cache-Control", "no-cache");
      response.setCharacterEncoding("UTF-8");
      String filepath ="E:/pic/";//文件上传的路径,实际开发中一般用相对路径
      String filename = "";
      String name="";
      ServletInputStream in = request.getInputStream();
      byte[] buf = new byte[4048];
      int len = in.readLine(buf, 0, buf.length);
      String f = new String(buf, 0, len - 1);
      while ((len = in.readLine(buf, 0, buf.length)) != -1) {
        filename = new String(buf, 0, len,"utf-8");//解决汉字乱码问题
        int j = filename.lastIndexOf("\"");
        int s = filename.indexOf("filename");
        name=filename.substring(s+10,j);
        filename = name;//通过上述处理可以得到上传的文件名
        System.out.println("filename="+filename);
                                                          
        DataOutputStream fileStream = new DataOutputStream(new BufferedOutputStream(new FileOutputStream(filepath+ filename)));
        len = in.readLine(buf, 0, buf.length);
        len = in.readLine(buf, 0, buf.length);
        while ((len = in.readLine(buf, 0, buf.length)) != -1) {
          String tempf = new String(buf, 0, len - 1);
          if (tempf.equals(f) || tempf.equals(f + "--")) {
            break;
          }
          else{
             fileStream.write(buf, 0, len); // 写入
          }
        }
        fileStream.close();
      }
      PrintWriter out=response.getWriter();
      String result = filename ;
      out.print(result);
      out.close();
      in.close();                       
  }
}

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持。

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