1 fileUpload.html
<html>
<head>
<title>文件上传</title>
</head>
<body>
<form action="fileUploadServlet" method="post" enctype="multipart/form-data">
<input type="file" name="file1" /><br>
<input type="submit"/>
</form>
</body>
</html>
2 FileUploadServlet
package com.li.servlet;
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;
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.File;
import java.io.IOException;
import java.util.List;
/**
* @author li
* @version 1.0
* @ClassName FileUploadServlet
* @date 2019/7/18 9:19
*/
@WebServlet("/fileUploadServlet")
public class FileUploadServlet extends HttpServlet {
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String path = getServletContext().getRealPath("/WEB-INF/upload");
File file = new File(path);
if(!file.isDirectory() && !file.exists()){
file.mkdir();
}
Boolean flag = ServletFileUpload.isMultipartContent(request);
if(flag){
FileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
try {
List<FileItem> items = upload.parseRequest(request);
for (FileItem item : items) {
if(!item.isFormField()){
String filename = item.getName();
if(filename.equals("")|| filename == null){
request.setAttribute("msg","文件为空");
request.getRequestDispatcher("fileResult.jsp").forward(request, response);
return;
}
File fileUp = new File(path,filename);
item.write(fileUp);
}
}
request.setAttribute("msg","文件上传成功");
request.getRequestDispatcher("fileResult.jsp").forward(request, response);
} catch (FileUploadException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
3 fileResult.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<a href="fileUpload.html">返回文件上传</a>
<br>
<p>${msg}</p>
</body>
</html>
测试
1 上传空文件 2 上传文件
