Question

问题陈述

从Spring 4迁移到Spring 3会导致异常处理流程中出现一些异常。异常在No suitable resolver for argument类中说org.springframework.web.method.support.InvocableHandlerMethod。

因此，无论何时发生异常，Spring都会尝试查找它获得的异常处理程序但是当它尝试填充方法参数或异常处理程序时，它会抛出以下异常

无法调用@ExceptionHandler方法：

  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)

基本上是@CRequestParam("p") String p变量

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;
    }

注解

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

Param Resolver

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

通过在请求中传递自定义参数来解决问题。

代码如下：

<强>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;

}

完整源代码可在git

获取

Answer 2

通过提供WebApplicationInitializer

的实现解决了这个问题

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);

}

Spring 4异常处理：没有合适的解析器用于参数

2 个答案: