Question

我想使用jsp和servlet将多个图像上传到服务器文件夹

我可以上传单张图片，但我无法上传多张图片

请帮帮我

Answer 1

尝试下面的代码（Apache commons文件上传）

index.jsp

<html>
 <head><title>Upload page</title></head><body>
 <form action="UploadServlet" method="post" enctype="multipart/form-data" name="form1" id="form1">
   <center>
   <table border="1">
       <tr>
           <td align="center"><b>Multipale file Uploade</td>
       </tr>
       <tr>
           <td>
               Select file: <input name="file" type="file" id="file">
           </td>
       </tr>
       <tr>
          <td>
             Select file:<input name="file" type="file" id="file">
          </td>
        <tr>
           <td>
              Select file:<input name="file" type="file" id="file">
           </td>
         </tr>
         <tr>
            <td align="center">
               <input type="submit" name="Submit" value="Submit files"/>
            </td>
         </tr>
    </table>
    <center>
 </form>
 </body>
 </html>

或者你也可以使用下面的代码用于jsp（如果你使用这个代码按ctrl 来选择多个图像）

<html>
 <head><title>Upload page</title></head><body>
 <form action="UploadServlet" method="post" enctype="multipart/form-data" name="form1" id="form1">
   <center>
   <table border="1">
       <tr>
           <td align="center"><b>Multipale file Uploade</td>
       </tr>
       <tr>
           <td>
               Specify file: <input name="file" type="file" id="file" multiple>
           </td>
       </tr>
         <tr>
            <td align="center">
               <input type="submit" name="Submit" value="Submit files"/>
            </td>
         </tr>
    </table>
    <center>
 </form>
 </body>
 </html>

和UploadServlet.java

package com;

import java.io.File;
import java.io.IOException;
import java.util.Iterator;
import java.util.List;

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 org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

@WebServlet("/UploadServlet")
public class UploadServlet extends HttpServlet {
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request, response);
    }

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        boolean isMultipart = ServletFileUpload.isMultipartContent(request);
        if (!isMultipart) {
        } else {
            FileItemFactory factory = new DiskFileItemFactory();
            ServletFileUpload upload = new ServletFileUpload(factory);
            List items = null;
            try {
                items = upload.parseRequest(request);
                } catch (FileUploadException e) {
                    e.printStackTrace();
                }
            Iterator itr = items.iterator();
            while (itr.hasNext()) {
                FileItem item = (FileItem) itr.next();
                if (item.isFormField()) {
                } else {
                    try {
                    String itemName = item.getName();
                    File savedFile = new File("D:\\"+itemName);
                    item.write(savedFile);  
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }
    }
}

希望这有帮助!!!

Answer 2

以下是示例代码：

Coding for uploadform.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"     "http://www.w3.org/TR/html4/loose.dtd"> 
<html>
<head>
  <title>Image Upload</title>
  <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
</head>
<body>
<form action="FileUploadServlet" method="post" enctype="multipart/form-data">
    <table width="400px" align="center" border=0>
       <tr>
       <td align="center" colspan=2>
            Image Details</td>
       </tr>
       <tr>
           <td>First Name </td>
       <td>
           <input type="input" name="firstname">
       </td>
   </tr>
   <tr>
       <td>Last Name </td>
       <td>
           <input type="input" name="lastname">
       </td>
   </tr>
   <tr>
       <td>Image Link: </td>
       <td>
           <input type="file" name="file">
       </td>
   </tr>
   <tr>
       <td></td>
       <td>
          <input type="submit" name="submit" value="Submit"></td>
       </tr>
   </table>
</form>
</body>
</html>

You need to set enctype of form tag to "multipart/form-data" it tells     that form contain multipart data.
This page contain two text fields for first name and last name and one file type field for files, after submitting the form data send to FileUploadServlet servlet where all other processing is to be done.

Coding for FileUploadServlet.java:


import java.io.PrintWriter;
import java.sql.*;
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("/FileUploadServlet")
@MultipartConfig(fileSizeThreshold=1024*1024*2, // 2MB
             maxFileSize=1024*1024*10,      // 10MB
             maxRequestSize=1024*1024*50)

public class FileUploadServlet extends HttpServlet {
private static final String SAVE_DIR="images";



protected void doPost(HttpServletRequest request, HttpServletResponse    response)
        throws ServletException, IOException, ClassNotFoundException,     SQLException {
    response.setContentType("text/html;charset=UTF-8");
    PrintWriter out = response.getWriter();
        String savePath = "C:" + File.separator + SAVE_DIR;
            File fileSaveDir=new File(savePath);
            if(!fileSaveDir.exists()){
                fileSaveDir.mkdir();
            }
        String firstName=request.getParameter("firstname");
        String lastName=request.getParameter("lastname");
        Part part=request.getPart("file");
        String fileName=extractFileName(part);
        part.write(savePath + File.separator + fileName);
       /* 
        //You need this loop if you submitted more than one file 
        for (Part part : request.getParts()) {
        String fileName = extractFileName(part);
        part.write(savePath + File.separator + fileName);
    }*/
       try
{
Class.forName("com.mysql.jdbc.Driver");
Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306    /UploadFile","root","root");
        String query="INSERT INTO customerDetail (first_name, last_name, file) values (?, ?, ?)";

            PreparedStatement pst;
            pst=con.prepareStatement(query);
            pst.setString(1, firstName);
            pst.setString(2,lastName);
            String filePath= savePath + File.separator + fileName ;
            pst.setString(3,filePath);
            pst.executeUpdate();
}
catch(Exception e)
        {}
}
    // file name of the upload file is included in content-disposition     header like this:
//form-data; name="dataFile"; filename="PHOTO.JPG"
private String extractFileName(Part part) {
    String contentDisp = part.getHeader("content-disposition");
    String[] items = contentDisp.split(";");
    for (String s : items) {
        if (s.trim().startsWith("filename")) {
            return s.substring(s.indexOf("=") + 2, s.length()-1);
        }
    }
    return "";
}
}

如何使用jsp和servlet将多个图像上传到文件夹中

2 个答案: