alexcuesta

The best way of handling errors in Spring MVC is implementing HandlerExceptionResolver interface or using the annotation @ExceptionHandler.

Here you have an example using DefaultHandlerExceptionResolver, the default implementation of HandlerExceptionResolver.

public class MyExceptionResolver extends DefaultHandlerExceptionResolver {

	@Override
	protected ModelAndView doResolveException(HttpServletRequest request,
			HttpServletResponse response,
			Object handler,
			Exception ex) {
		
		try {
			if (ex instanceof PossibleSpamException) {
				return handlePossibleSpamException((PossibleSpamException) ex, request, response);
			} 
		}
		catch (Exception handlerException) {
			logger.warn("Handling of [" + ex.getClass().getName() + "] resulted in Exception", handlerException);
		}
		
		return super.doResolveException(request, response, handler, ex);
	}
	
	private ModelAndView handlePossibleSpamException(PossibleSpamException ex,
			HttpServletRequest request,
			HttpServletResponse response) throws Exception {

		response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE);  // HTTP Status code 503
		return new ModelAndView();
	}
	
}

This resolver is defined in the applicationContext.xml:

<bean id="exceptionResolver" class="domain.MyExceptionResolver" />

And the corresponding JSP is declared in web.xml:

<error-page>
	<error-code>503</error-code>
	<location>/WEB-INF/views/errors/503.jsp</location>
</error-page>