Servlet 文件上传
发布者 : @gmail | 发布时间 : 2019-01-05 11:51:20文章号 : 10 | 阅读量 : 4+1 | AAW值(?) : 10.50 (仅供参考)
upload.jsp
<%--
Created by IntelliJ IDEA.
User: adler
Date: 2018/11/10
Time: 4:20 PM
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Upload Files</title>
</head>
<body>
<form method="post"action="/Uploader" enctype="multipart/form-data">
选择文件:
<br>
<input type="file"name="uploadFile"/>
<br>
<input type="submit"value="上传"/>
</form>
</body>
</html>
Uploader.java
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
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.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
/**
* Servlet implementation class UploadServlet
*/
@WebServlet("/Uploader")
public class Uploaderextends HttpServlet {
private static final long serialVersionUID = 1L;
//上传文件存储目录
private static final String UPLOAD_DIRECTORY= "upload";
//上传配置
private static final int MEMORY_THRESHOLD =1024 * 1024 * 3; // 3MB
private static final int MAX_FILE_SIZE =1024 * 1024 * 40; // 40MB
private static final int MAX_REQUEST_SIZE =1024 * 1024 * 50; // 50MB
/**
* 上传数据及保存文件
*/
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throwsServletException, IOException {
//检测是否为多媒体上传
if(!ServletFileUpload.isMultipartContent(request)) {
//如果不是则停止
PrintWriter writer = response.getWriter();
writer.println("Error: 表单必须包含enctype=multipart/form-data");
writer.flush();
return;
}
//配置上传参数
DiskFileItemFactory factory = new DiskFileItemFactory();
//设置内存临界值- 超过后将产生临时文件并存储于临时目录中
factory.setSizeThreshold(MEMORY_THRESHOLD);
//设置临时存储目录
factory.setRepository(new File(System.getProperty("java.io.tmpdir")));
ServletFileUpload upload = new ServletFileUpload(factory);
//设置最大文件上传值
upload.setFileSizeMax(MAX_FILE_SIZE);
//设置最大请求值(包含文件和表单数据)
upload.setSizeMax(MAX_REQUEST_SIZE);
//中文处理
upload.setHeaderEncoding("UTF-8");
//构造临时路径来存储上传的文件
// 这个路径相对当前应用的目录
String uploadPath = request.getServletContext().getRealPath("./") + File.separator + UPLOAD_DIRECTORY;
//如果目录不存在则创建
File uploadDir = new File(uploadPath);
if(!uploadDir.exists()) {
uploadDir.mkdir();
}
try{
//解析请求的内容提取文件数据
@SuppressWarnings("unchecked")
List<FileItem> formItems = upload.parseRequest(request);
if(formItems != null&& formItems.size() > 0) {
// 迭代表单数据
for (FileItem item : formItems) {
// 处理不在表单中的字段
if (!item.isFormField()) {
String fileName =new File(item.getName()).getName();
String filePath = uploadPath + File.separator + fileName;
File storeFile = new File(filePath);
// 在控制台输出文件的上传路径
System.out.println(filePath);
// 保存文件到硬盘
item.write(storeFile);
request.setAttribute("message",
"文件上传成功!");
}
}
}
} catch(Exception ex) {
request.setAttribute("message",
"错误信息: " + ex.getMessage());
}
//跳转到message.jsp
request.getServletContext().getRequestDispatcher("/message.jsp").forward(
request, response);
}
}
message.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type"content="text/html; charset=UTF-8">
<title>文件上传结果</title>
</head>
<body>
<center>
<h2>${message}</h2>
</center>
</body>
</html>
