Spring 4异常处理:没有合适的参数解析程序

Question

问题陈述

从Spring 3迁移到Spring 4会在异常处理流程中引发一些异常。Exception在org.springframework.web.method.support.InvocableHandlerMethod类中显示No suitable resolver for argument。

因此，每当发生异常时，Spring都会尝试找到它得到的异常处理程序但是当它试图填充方法参数或异常处理程序时，它会抛出以下异常

调用@ExceptionHandler方法失败：

  public org.springframework.web.servlet.ModelAndView  
       HelloController.handleCustomException(CustomGenericException, javax.servlet.http.HttpServletRequest, org.springframework.web.servlet.ModelAndView)
  java.lang.IllegalStateException: 
     No suitable resolver for argument [2] 
             [type=org.springframework.web.servlet.ModelAndView]

HandlerMethod详细信息：

Controller [HelloController]
Method [public org.springframework.web.servlet.ModelAndView  
        HelloController.handleCustomException(CustomGenericException,
            javax.servlet.http.HttpServletRequest,org.springframework.web.servlet.ModelAndView)]
        at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(
                     InvocableHandlerMethod.java:169)

它主要用于@CRequestParam("p") String p可变

代码

控制器

@RequestMapping(method = RequestMethod.GET, value="/exception2")
    public String getException1(ModelMap model, @CRequestParam("p") String p) {
        System.out.println("Exception 2 "+ p);
        throw new CustomGenericException("1","2");
    }

异常处理程序

@ExceptionHandler(CustomGenericException.class)
    public ModelAndView handleCustomException(CustomGenericException ex, 
            HttpServletRequest request, @CRequestParam("p") String p) {
            ModelAndView model = new ModelAndView("error/generic_error");
            model.addObject("exception", ex);
            System.out.println("CustomGenericException  ");
            return model;
    }

注释

@Target( { ElementType.PARAMETER })
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface CRequestParam {
    String value() default "";
}

参数解析程序

public class CRequestparamResolver implements HandlerMethodArgumentResolver {

    @Override
        public boolean supportsParameter(MethodParameter methodParameter) {
          CRequestParam requestParamAnnotation = 
          methodParameter.getParameterAnnotation(CRequestParam.class);
        if(requestParamAnnotation==null){
        return false;
        }
        return true;
        }
    @Override
    public Object resolveArgument(MethodParameter methodParameter,
        ModelAndViewContainer mavContainer, NativeWebRequest webRequest,
        WebDataBinderFactory binderFactory) throws Exception {
    CRequestParam requestParamAnnotation = methodParameter .getParameterAnnotation(CRequestParam.class);
    if (requestParamAnnotation != null) {
        String requestParamName = requestParamAnnotation.value();
        if (StringUtils.hasText(requestParamName)) {
        return webRequest.getParameter(requestParamName);
        }
    }
    return null;
  }

XML配置

<bean
        class="com.mkyong.common.resolver.AnnotationMethodHandlerAdapterConfigurer"
        init-method="init">
        <property name="customArgumentResolvers">
            <list>
                <bean class="com.mkyong.common.resolver.CRequestparamResolver" />
            </list>
        </property>
    </bean>
    <bean 
 class="org.springframework.web.servlet.mvc.method.annotation.ExceptionHandlerExceptionResolver">
        <property name="customArgumentResolvers">
            <list>
                <bean class="com.mkyong.common.resolver.CRequestparamResolver" />
            </list>
        </property>
    </bean>

源代码

https://github.com/santoshjoshi/SpringMVC4

Answer 1

通过在请求本身中传递自定义参数来解决问题。

代码如下：

控制器

@RequestMapping(method = RequestMethod.GET, value = "/exception2")
public String getException1(ModelMap model, @CRequestParam("p") String p, HttpServletRequest request) {
  System.out.println("Exception 2 " + p);
  request.setAttribute("p", p);
  throw new CustomGenericException("1", "2");
}

异常处理程序

@ExceptionHandler(CustomGenericException.class)
public ModelAndView handleCustomException(CustomGenericException ex, HttpServletRequest request) {
  ModelAndView model2 = new ModelAndView("error/generic_error");
  model2.addObject("exception", ex);
  System.out.println(request.getAttribute("p"));
  System.out.println("CustomGenericException  ");
  return model2;
}

完整的源代码可在git 上获得

Answer 2

在我的情况下，我没有将@RequestBody添加到我的客户端界面，所以它不知道如何解析参数。

Answer 3

通过提供WebApplicationInitializer 的实现解决了问题

public class SpringDispatcherConfig implements WebApplicationInitializer {
@Override
public void onStartup(ServletContext servletContext) throws ServletException {
    AnnotationConfigWebApplicationContext Contianer =   new AnnotationConfigWebApplicationContext();
    Contianer.register(SpringConfig.class);
    Contianer.setServletContext(servletContext);
    DispatcherServlet dispatcherServlet = new DispatcherServlet(Contianer);
    dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);
    Dynamic servlet = servletContext.addServlet("spring",dispatcherServlet);
    servlet.addMapping("/");
    servlet.setLoadOnStartup(1);
}