如何找出@ExceptionHandler不起作用的原因？

Question

在我的项目中，当我在控制器中添加异常处理程序方法时，它不起作用。但是如果我将此代码移到具有相同Spring版本的演示项目中，missingParamterHandler方法可以很好地工作。有人能帮我处理这个问题吗？

@Controller
@RequestMapping("/order")
public class OrderControlle{

    @ExceptionHandler(Exception.class)
    public @ResponseBody ClientResult missingParamterHandler(Exception exception) {
    /*inspect and exception and obtain meaningful message*/
    ClientResult clientResult = new ClientResult();
    clientResult.getBstatus().setCode(BstatusCode.PARAM_ERR);
    return clientResult; 
    }
}

private void initHandlerExceptionResolvers(ApplicationContext context) {
    this.handlerExceptionResolvers = null;

    if (this.detectAllHandlerExceptionResolvers) {
        // Find all HandlerExceptionResolvers in the ApplicationContext, including ancestor contexts.
        Map<String, HandlerExceptionResolver> matchingBeans = BeanFactoryUtils
                .beansOfTypeIncludingAncestors(context, HandlerExceptionResolver.class, true, false);
        if (!matchingBeans.isEmpty()) {
            this.handlerExceptionResolvers = new ArrayList<HandlerExceptionResolver>(matchingBeans.values());
            // We keep HandlerExceptionResolvers in sorted order.
            OrderComparator.sort(this.handlerExceptionResolvers);
        }
    }
    .....

Answer 1

显式地将 <bean class="“org.springframework.web.servlet.mvc.method.annotation.exceptionHandlerExceptionResolver”/">或 添加到app-context.xml中，解决了我的问题。

如果没有上面这一行，spring在我的项目中添加了如下所示的ExceptionResolvers。

org.springframework.web.servlet.HandlerExceptionResolver=org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerExceptionResolver,\
org.springframework.web.servlet.mvc.annotation.ResponseStatusExceptionResolver,\
org.springframework.web.servlet.mvc.support.DefaultHandlerExceptionResolver