Spring MVC 文件上传

<!-- SpringMVC上传文件时，需要配置MultipartResolver处理器 -->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="UTF-8"/>
        <!-- 指定所上传文件的总大小不能超过200KB。注意maxUploadSize属性的限制不是针对单个文件，而是所有文件的容量之和 -->
        <property name="maxUploadSize" value="200000"/>
    </bean>

    <!-- SpringMVC在超出上传文件限制时，会抛出org.springframework.web.multipart.MaxUploadSizeExceededException -->
    <!-- 该异常是SpringMVC在检查上传的文件信息时抛出来的，而且此时还没有进入到Controller方法中 -->
    <bean id="exceptionResolver" class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver">
        <property name="exceptionMappings">
            <props>
                <!-- 遇到MaxUploadSizeExceededException异常时，自动跳转到/WEB-INF/ftl/common/error_fileupload.ftl页面 -->
                <prop key="org.springframework.web.multipart.MaxUploadSizeExceededException">/common/error_fileupload</prop>
            </props>
        </property>
    </bean>

package com.zyz.action;

import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.util.Date;

/**
 * Created by zyz on 2016-8-26.
 */

@Controller
public class UploadAction {

    @RequestMapping(value = "/uploadform",method = RequestMethod.GET)
    public String uploadForm(){
        return "uploadForm";
    }

    @RequestMapping(value = "/upload",method = RequestMethod.POST)
    public String upload(@RequestParam(value = "file", required = false) MultipartFile file, HttpServletRequest request, ModelMap model) {

        System.out.println("开始");
        String path = request.getSession().getServletContext().getRealPath("upload");
//        String fileName = file.getOriginalFilename();
        String fileName = new Date().getTime()+".jpg";
        System.out.println(path);
        File targetFile = new File(path, fileName);
        if(!targetFile.exists()){
            targetFile.mkdirs();
        }

        //保存
        try {
            file.transferTo(targetFile);
        } catch (Exception e) {
            e.printStackTrace();
        }
        model.addAttribute("fileUrl", request.getContextPath()+"/upload/"+fileName);
        return "uploadResult";
    }

}