@ExceptionHandler on CGLib-proxied controller is ineffectual [SPR-5959]

[spring-projects-issues]

William Ashley opened SPR-5959 and commented

Here is a condensed example of the problem I'm encountering:

Controller:

package com.test;

import java.io.PrintWriter;

import org.springframework.stereotype.Controller;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
@Transactional( readOnly=true )
public class Test
{
	@ExceptionHandler
	public void exception( Throwable t )
	{
		System.out.println( "In exception handler" );
	}
	
	@RequestMapping( "/" )
	public void get()
	{
		throw new RuntimeException( "foo" );
	}
}

Dispatcher servlet config:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd">
	
	<tx:annotation-driven transaction-manager="transactionManager"/>
	<bean id="transactionManager" class="com.test.MockTransactionManager"/>
	
	<context:component-scan base-package="com.test"/>
	
</beans>

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_5.xsd"
	version="2.5">
	
	<servlet>
		<servlet-name>action</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<load-on-startup>1</load-on-startup>
	</servlet>
	<servlet-mapping>
		<servlet-name>action</servlet-name>
		<url-pattern>/*</url-pattern>
	</servlet-mapping>
	
</web-app>

The exception handler is never invoked when the controller is proxied by CGLib (removing @Transactional removes the proxy and restores the exception handler). A little digging led me to org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerExceptionResolver where there is this iteration over methods of the controller

		ReflectionUtils.doWithMethods(handlerType, new ReflectionUtils.MethodCallback() {
			public void doWith(Method method) {
				method = ClassUtils.getMostSpecificMethod(method, handlerType);
[snip]
			}
		});

which does arrive eventually at the proper exception handler method of my controller class, but because of the call to ClassUtils.getMostSpecificMethod() it winds up back at the overridden method on the CGLib-generated class (which from what I noticed it had already visited). I haven't researched enough to say this is the problem though.

@RequestMapping annotations appear to work normally through a proxied controller (and the @Transactional annotation does function correctly), so I'm hoping this can be fixed.

---

Affects: 3.0 M3

Issue Links:

• MVC Annotation Inheritance [SPR-6093] #10761 MVC Annotation Inheritance ("duplicates")
• @ExceptionHandler doesn't work on CGLib-proxied controller in Portlet MVC [SPR-7337] #11996 @ExceptionHandler doesn't work on CGLib-proxied controller in Portlet MVC

1 votes, 2 watchers

[spring-projects-issues]

William Ashley commented

Sorry, I should have commented earlier. This was fixed as part of #10761 which was superset of this bug.

[spring-projects-issues]

Arjen Poutsma commented

Great! If only all resolutions were so simple... :)