上传接口：

package net.jcshop.core.servlet;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.Random;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.disk.DiskFileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.fileupload.util.Streams;
import org.springframework.web.bind.annotation.RequestMapping;

import com.alibaba.fastjson.JSONObject;

/**
 * jQuery文件上传插件
 * @author Administrator
 *
 */
public class Uploadify extends HttpServlet{
    private static final long serialVersionUID = 1L;  
      
    /** 
     * 实现多文件的同时上传 
     */   
    public void doGet(HttpServletRequest request,  
            HttpServletResponse response) throws ServletException, IOException {  
         System.out.println("===========");
        //设置接收的编码格式  
        request.setCharacterEncoding("UTF-8");  
        Date date = new Date();//获取当前时间  
        String fileRealPath = "";//文件存放真实地址  
          
        String fileRealResistPath = "";//文件存放真实相对路径  
        //文件保存目录URL
        String saveUrl  = "/attached/"; 
        String firstFileName="";  
        // 获得容器中上传文件夹所在的物理路径  
        String savePath = this.getServletConfig().getServletContext().getRealPath("/") + "attached/";
        //创建文件夹
        savePath +="image" + "/";
        saveUrl +="image" + "/";
        File saveDirFile = new File(savePath);
        if (!saveDirFile.exists()) {
            saveDirFile.mkdirs();
        }
        SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
        String ymd = sdf.format(new Date());
        savePath += "comment/"+ymd + "/";
        saveUrl += "comment/"+ymd + "/";
        File file = new File(savePath);  
        if (!file.isDirectory()) {  
            file.mkdirs();  
        }  
  
        try {  
            DiskFileItemFactory fac = new DiskFileItemFactory();  
            ServletFileUpload upload = new ServletFileUpload(fac);  
            upload.setHeaderEncoding("UTF-8");
//            upload.setFileItemFactory(factory)
            System.out.println("request：＝"+request);
            // 获取多个上传文件  
            List fileList = fileList = upload.parseRequest(request);
           //获取多个图片地址字符串
            StringBuilder sb = new StringBuilder();
            System.out.println("fileList:"+fileList);
            // 遍历上传文件写入磁盘  
            Iterator it = fileList.iterator();  
            while (it.hasNext()) {  
                Object obit = it.next();
                if(obit instanceof DiskFileItem){
                    System.out.println("xxxxxxxxxxxxx");
                    DiskFileItem item = (DiskFileItem) obit;  
                      
                    // 如果item是文件上传表单域     
                    // 获得文件名及路径     
                    String fileName = item.getName();
                    String newFileName=null;
                    if (fileName != null) {  
                        firstFileName=item.getName().substring(item.getName().lastIndexOf("\\")+1);  
                        String formatName = firstFileName.substring(firstFileName.lastIndexOf("."));//获取文件后缀名  
                        SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmmss");
                        newFileName = df.format(new Date()) + "_" + new Random().nextInt(1000) + formatName;
                        fileRealPath = savePath + newFileName;//+ formatName;//文件存放真实地址  
                          
                        BufferedInputStream in = new BufferedInputStream(item.getInputStream());// 获得文件输入流  
                        BufferedOutputStream outStream = new BufferedOutputStream(new FileOutputStream(new File(fileRealPath)));// 获得文件输出流  
                        Streams.copy(in, outStream, true);// 开始把文件写到你指定的上传文件夹  
                        //上传成功，则插入数据库  
                        if (new File(fileRealPath).exists()) {
                            fileRealResistPath=saveUrl+newFileName;
                            sb.append(fileRealResistPath+",");
                            //保存到数据库  
                            System.out.println("保存到数据库:");  
                            System.out.println("虚拟路径:"+fileRealResistPath);  
                        }  
                           
                    }   
                }
            }
            sb.deleteCharAt(sb.length()-1);
            JSONObject obj = new JSONObject();
            obj.put("state", "ok");
            obj.put("message",sb.toString());
            response.getWriter().print(obj.toString());
            System.out.println("保存路径:"+sb.toString());  
        } catch (org.apache.commons.fileupload.FileUploadException ex) {
           ex.printStackTrace();
           JSONObject obj = new JSONObject();
           obj.put("state", "error");
           obj.put("message","没有上传文件");
           System.out.println("没有上传文件");
           response.getWriter().write(obj.toJSONString());
           return;  
        }   
     //  response.getWriter().write("error");  
          
    }  
   
    public void doPost(HttpServletRequest req, HttpServletResponse resp)  
            throws ServletException, IOException {  
        doGet(req, resp);  
    } 
}

web.xml配置 url

    <servlet>
        <servlet-name>Uploadify</servlet-name>
        <servlet-class>net.jcshop.core.servlet.Uploadify</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>Uploadify</servlet-name>
        <url-pattern>/uploadify.do</url-pattern>
    </servlet-mapping>