基于SSM框架的文件上传

<form action="upload" encType="multipart/form-data" method="post">
    <label>选择文件</label>
    <input id="fileId" name="file" type="file"/>
    <input type="submit" value="提交"/>    
</form>

@RequestMapping("/upload")
    public String uploadImg(HttpServletRequest request) throws IllegalStateException, IOException
    {
        //拼接文件存储的目录
        String temp=Thread.currentThread().getContextClassLoader().getResource("").getPath(); 
        int num=temp.indexOf(".metadata");
        String path=temp.substring(1,num).replace(‘/‘, ‘\\‘)+request.getContextPath().replaceAll("/", "")+"\\WebContent\\images\\";
        
        //上传文件
        List<String> list = FileUtil.upLoad(request, path);
        request.setAttribute("path", list.get(0));
        System.out.println(list.get(0));
       return "uploadok"; 
        
    }

package com.yck.util;

import java.io.File;
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.UUID;

import javax.servlet.http.HttpServletRequest;

import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;
import org.springframework.web.multipart.commons.CommonsMultipartResolver;

public class FileUtil
{
    
    public static List<String> upLoad(HttpServletRequest request,String path)
    {
        
        List<String> list = new ArrayList<String> ();    //存放结果
        //1、将当前上下文初始化给CommonMutipartResolver
        CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver(request.getSession().getServletContext());
        //2、检查Form中encType是否为multipart/form-data
        if(multipartResolver.isMultipart(request))
        {
            //将request转为MultipartHttpServletRequest
            MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;
            //获取迭代器遍历multipartRequest里的文件名
            Iterator<String> iter = multipartRequest.getFileNames();
            while(iter.hasNext())
            {
                //获取文件并向下遍历
                MultipartFile file = multipartRequest.getFile(iter.next().toString());
                if(file != null)
                {
                    //获取文件类型，即后缀名
                    String str = file.getOriginalFilename();
                    String suffix = str.substring(str.lastIndexOf("."));
                    
                    //用 当前日期+UUID作为文件名避免重名
                    SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");
                    String dateStr = sdf.format(new Date()).replaceAll("-", "");
                    String name = dateStr +UUID.randomUUID().toString().replaceAll("-", "");
                    
                    //拼接文件绝对路径
                    String filePath = path + name + suffix;
                    try
                    {
                        file.transferTo(new File(filePath));
                    } catch (IllegalStateException | IOException e)
                    {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                    list.add(filePath);
                }
            }
        }
        return list;
        
    }

}