jsp前端form表单请求不到controller是为什么，求大佬看一下

为什么这个表单提交之后到不了controller层，是不是action的问题 ，我尝试了好多种action的写法都是报404。。。代码比较乱恳请大佬帮忙看一下

这是前端的form表单的代码

<form action="${pageContext.request.contextPath}/imageRecognition/adgct/adg" method="post"  id="formimg" name="img" >
  <div class="col-md-1"></div>
  <div class="input-group col-md-9">
  <input name="imgName" value="${keyword }" class="form-control input-lg" placeholder="请将图片放入指定文件，并输入图片名字" type="text" id="imgName">
   <span class="input-group-btn"><button class="btn btn-primary input-lg" type="submit"><strong><span class="glyphicon glyphicon-search" ></span> 识别</strong></button></span>
  </div>
  </form>

这个是controller的代码

@RequestMapping("/imageRecognition/adgct")
@Controller
public class adgController {


    @RequestMapping(value="/adg",method=RequestMethod.POST)
    public ModelAndView adg(Img img) {
        ModelAndView mv = new ModelAndView();
        String imgName = img.getImgName();
        System.out.println(imgName);
        AdvancedGeneral adv = new AdvancedGeneral();
        String kwd = adv.advancedGeneral(imgName);
        mv.setViewName("home/search");
        mv.addObject("k", kwd);
        mv.addObject("keyword", kwd);
        return mv;

    }

}

把action属性的值的${pageContext.request.contextPath}去掉。