JSP 组件上传文件（common fileupload）

第1个上传组件commons-fileupload
=============commons-fileupload ================
common-fileupload组件是apache的一个开源项目之一，可以从http://jakarta.apache.org/commons/fileupload/下载。该组件简单易用，可实现一次上传一个或多个文件，并可限制文件大小。
-下载后解压zip包，将commons-fileupload-1.1.1.jar,和commons-io-1.2.jar复制到tomcat的webapps\你的webapp\WEB-INF\lib\下，如果目录不存在请自建目录。
新建一个servlet: FileUpload.java用于文件上传：
package com.drp.util.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.*;
import java.util.*;
import java.util.regex.*;
import java.io.*;
import org.apache.commons.fileupload.servlet.*;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
public class FileUpload extends HttpServlet {
private String uploadPath = ""; // 用于存放上传文件的目录
private File tempPath = new File("D:\\Tomcat 5.5\\webapps\\drp1.2\\tempimages\\"); // 用于存放临时文件的目录
public void doPost(HttpServletRequest req, HttpServletResponse res)
    throws ServletException, IOException {
   res.setContentType("text/html; charset=GB18030");
   PrintWriter out = res.getWriter();
   System.out.println(req.getContentLength());
   System.out.println(req.getContentType());
   DiskFileItemFactory factory = new DiskFileItemFactory();
   // maximum size that will be stored in memory
  //允许设置内存中存储数据的门限，单位：字节
   factory.setSizeThreshold(4096);
   // the location for saving data that is larger than getSizeThreshold()
//如果文件大小大于SizeThreshold，则保存到临时目录
   factory.setRepository(new File("D:\\Tomcat 5.5\\webapps\\drp1.2\\tempimages"));
   ServletFileUploa