首先，跟上传一般文件一样，需要写一个servlet来处理上传的文件，你可以修改保存路径或选择将图片保存在数据库中，只需要做简单的修改就行了，servlet代码如下：

package com.ek.servlet;

import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.servlet.ServletException;
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.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

import com.ek.image.ImageUtil;

public class FileUploadServlet extends HttpServlet {

/**
*?
*/
private static final long serialVersionUID = 1L;

private static String filePath = "";

/**
* Destruction of the servlet. <br>
*/

public void destroy() {
?? super.destroy(); // Just puts "destroy" string in log
?? // Put your code here
}

/**
* The doPost method of the servlet. <br>
*?
* This method is called when a form has its tag value method equals to
* post.
*?
* @param request
*??????????? the request send by the client to the server
* @param response
*??????????? the response send by the server to the client
* @throws ServletException
*???????????? if an error occurred
* @throws IOException
*???????????? if an error occurred
*/
public void doPost(HttpServletRequest req, HttpServletResponse res)
??? throws ServletException, IOException {
?? res.setContentType("text/html; charset=UTF-8");
?? DiskFileItemFactory factory = new DiskFileItemFactory();
?? // maximum size that will be stored in memory
?? factory.setSizeThreshold(4096);
?? // the location for saving data that is larger than getSizeThreshold()
?? factory.setRepository(new File(filePath));

?? ServletFileUpload upload = new ServletFileUpload(factory);
?? // maximum size before a FileUploadException will be thrown
?? upload.setSizeMax(1000000);
?? try {
??? List fileItems = upload.parseRequest(req);

??? Iterator iter = fileItems.iterator();

??? // Get the file name
??? String regExp = ".+\\\\(.+\\.?())$";