Spriing mvc上传多文件

<form action="${pageContext.request.contextPath }/user/upload" method="post" enctype="multipart/form-data">
   	attach 1:<input type="file" name="attachs" /><br/>
attach 2:<input type="file" name="attachs"/><br/>
<button type="submit">提交</button>
</form>

@RequestMapping(value="/upload",method=RequestMethod.POST )
public String upload(@RequestParam("attachs") MultipartFile[] attachs,HttpServletRequest req){
String realPath=req.getSession().getServletContext().getRealPath("/resources/upload");//保存的路径
System.out.println(attachs.length);
System.out.println(realPath);
for(MultipartFile attach:attachs){
System.out.println(attach);
if(!attach.isEmpty()){
File file=new File(realPath+"/"+attach.getOriginalFilename());
try {
　　　　　　　　　　　　//底层数据io传输
attach.transferTo(file);
} catch (IllegalStateException | IOException e) {
e.printStackTrace();
}
}

}
return "welcome";
}

<!-- 配置MultipartResolver,用于上传文件，使用Spring的CommonsMultiparResolver -->
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<property name="maxUploadSize" value="5000000"/>
<property name="defaultEncoding" value="UTF-8"/>
</bean>