Apache Commons fileUpload实现文件上传之一_JAVA教程

Apache Commons fileUpload实现文件上传之一

2020-04-09 14:45mrr JAVA教程

这篇文章主要介绍了Apache Commons fileUpload实现文件上传之一的相关资料,需要的朋友可以参考下

废话不多说了，直奔主题了。

需要两个jar包：

commons-fileupload.jar

Commons IO的jar包（本文使用commons-io-2.4.jar）

利用Servlet来实现文件上传。

				?

									package web.servlet;

									import java.io.IOException;

									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.util.Iterator;

									import java.util.List;

									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("/UploadServlet")

									public class UploadServlet extends HttpServlet {

									private static final long serialVersionUID = 1L;

									private String uploadPath = "D:\\temp"; // 上传文件的目录

									private String tempPath = "d:\\temp\\buffer\\"; // 临时文件目录

									File tempPathFile;

									public void doPost(HttpServletRequest request, HttpServletResponse response)

									throws IOException, ServletException {

									try {

									// Create a factory for disk-based file items

									DiskFileItemFactory factory = new DiskFileItemFactory();

									// Set factory constraints

									factory.setSizeThreshold(4096); // 设置缓冲区大小，这里是4kb

									factory.setRepository(tempPathFile);// 设置缓冲区目录

									// Create a new file upload handler

									ServletFileUpload upload = new ServletFileUpload(factory);

									// Set overall request size constraint

									upload.setSizeMax(4194304); // 设置最大文件尺寸，这里是4MB

									List<FileItem> items = upload.parseRequest(request);// 得到所有的文件

									Iterator<FileItem> i = items.iterator();

									while (i.hasNext()) {

									FileItem fi = (FileItem) i.next();

									String fileName = fi.getName();

									if (fileName != null) {

									File fullFile = new File(fi.getName());

									File savedFile = new File(uploadPath, fullFile.getName());

									fi.write(savedFile);

									}

									}

									System.out.print("upload succeed");

									} catch (Exception e) {

									// 可以跳转出错页面

									e.printStackTrace();

									}

									}

									public void init() throws ServletException {

									File uploadFile = new File(uploadPath);

									if (!uploadFile.exists()) {

									uploadFile.mkdirs();

									}

									File tempPathFile = new File(tempPath);

									if (!tempPathFile.exists()) {

									tempPathFile.mkdirs();

									}

									}

									}

jsp

				?

									<%@ page language="java" contentType="text/html; charset=ISO--"

									pageEncoding="utf-"%>

									<!DOCTYPE html PUBLIC "-//WC//DTD HTML . Transitional//EN" "http://www.w.org/TR/html/loose.dtd">

									<html>

									<head>

									<meta http-equiv="Content-Type" content="text/html; charset=GB">

									<title>File upload</title>

									</head>

									<body>

									<!-- // action="fileupload"对应web.xml中<servlet-mapping>中<url-pattern>的设置. -->

									<form name="myform" action="UploadServlet" method="post"

									enctype="multipart/form-data">

									File:<br>

									<input type="file" name="myfile"><br>

									<br>

									<input type="submit" name="submit" value="Commit">

									</form>

									</body>

									</html>