@ExceptionHandler matches against cause type as well

Issue: SPR-14291

Author: jhoeller

spring-web/src/main/java/org/springframework/web/method/annotation/ExceptionHandlerMethodResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -31,14 +31,14 @@
 import org.springframework.util.ClassUtils;
 import org.springframework.util.ReflectionUtils.MethodFilter;
 import org.springframework.web.bind.annotation.ExceptionHandler;
-import org.springframework.web.util.NestedServletException;
 
 /**
  * Discovers {@linkplain ExceptionHandler @ExceptionHandler} methods in a given class,
  * including all of its superclasses, and helps to resolve a given {@link Exception}
  * to the exception types supported by a given {@link Method}.
  *
  * @author Rossen Stoyanchev
+ * @author Juergen Hoeller
  * @since 3.1
  */
 public class ExceptionHandlerMethodResolver {
@@ -126,8 +126,11 @@ public boolean hasExceptionMappings() {
 	 */
 	public Method resolveMethod(Exception exception) {
 		Method method = resolveMethodByExceptionType(exception.getClass());
-		if (method == null && exception instanceof NestedServletException && exception.getCause() != null) {
-			method = resolveMethodByExceptionType(exception.getCause().getClass());
+		if (method == null) {
+			Throwable cause = exception.getCause();
+			if (cause != null) {
+				method = resolveMethodByExceptionType(cause.getClass());
+			}
 		}
 		return method;
 	}

spring-webmvc/src/main/java/org/springframework/web/servlet/handler/AbstractHandlerMethodExceptionResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -34,7 +34,7 @@ public abstract class AbstractHandlerMethodExceptionResolver extends AbstractHan
 
 	/**
 	 * Checks if the handler is a {@link HandlerMethod} and then delegates to the
-	 * base class implementation of {@link #shouldApplyTo(HttpServletRequest, Object)}
+	 * base class implementation of {@code #shouldApplyTo(HttpServletRequest, Object)}
 	 * passing the bean of the {@code HandlerMethod}. Otherwise returns {@code false}.
 	 */
 	@Override
@@ -54,8 +54,7 @@ else if (handler instanceof HandlerMethod) {
 
 	@Override
 	protected final ModelAndView doResolveException(
-			HttpServletRequest request, HttpServletResponse response,
-			Object handler, Exception ex) {
+			HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) {
 
 		return doResolveHandlerMethodException(request, response, (HandlerMethod) handler, ex);
 	}
@@ -75,7 +74,6 @@ protected final ModelAndView doResolveException(
 	 * @return a corresponding ModelAndView to forward to, or {@code null} for default processing
 	 */
 	protected abstract ModelAndView doResolveHandlerMethodException(
-			HttpServletRequest request, HttpServletResponse response,
-			HandlerMethod handlerMethod, Exception ex);
+			HttpServletRequest request, HttpServletResponse response, HandlerMethod handlerMethod, Exception ex);
 
 }

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ExceptionHandlerExceptionResolver.java

@@ -65,6 +65,7 @@
  * {@link #setArgumentResolvers} and {@link #setReturnValueHandlers(List)}.
  *
  * @author Rossen Stoyanchev
+ * @author Juergen Hoeller
  * @since 3.1
  */
 public class ExceptionHandlerExceptionResolver extends AbstractHandlerMethodExceptionResolver
@@ -364,10 +365,10 @@ protected ModelAndView doResolveHandlerMethodException(HttpServletRequest reques
 			if (logger.isDebugEnabled()) {
 				logger.debug("Invoking @ExceptionHandler method: " + exceptionHandlerMethod);
 			}
-			if (exception.getCause() != null) {
-				// Expose root cause as provided argument as well
-				exceptionHandlerMethod.invokeAndHandle(
-						webRequest, mavContainer, exception, exception.getCause(), handlerMethod);
+			Throwable cause = exception.getCause();
+			if (cause != null) {
+				// Expose cause as provided argument as well
+				exceptionHandlerMethod.invokeAndHandle(webRequest, mavContainer, exception, cause, handlerMethod);
 			}
 			else {
 				// Otherwise, just the given exception as-is

spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/ExceptionHandlerExceptionResolverTests.java

@@ -25,6 +25,7 @@
 import org.junit.BeforeClass;
 import org.junit.Test;
 
+import org.springframework.beans.FatalBeanException;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -70,10 +71,10 @@ public class ExceptionHandlerExceptionResolverTests {
 
 	@BeforeClass
 	public static void setupOnce() {
-		ExceptionHandlerExceptionResolver r = new ExceptionHandlerExceptionResolver();
-		r.afterPropertiesSet();
-		RESOLVER_COUNT = r.getArgumentResolvers().getResolvers().size();
-		HANDLER_COUNT = r.getReturnValueHandlers().getHandlers().size();
+		ExceptionHandlerExceptionResolver resolver = new ExceptionHandlerExceptionResolver();
+		resolver.afterPropertiesSet();
+		RESOLVER_COUNT = resolver.getArgumentResolvers().getResolvers().size();
+		HANDLER_COUNT = resolver.getReturnValueHandlers().getHandlers().size();
 	}
 
 	@Before
@@ -220,9 +221,7 @@ public void resolveExceptionGlobalHandlerOrdered() throws Exception {
 		assertEquals("TestExceptionResolver: IllegalStateException", this.response.getContentAsString());
 	}
 
-	// SPR-12605
-
-	@Test
+	@Test  // SPR-12605
 	public void resolveExceptionWithHandlerMethodArg() throws Exception {
 		AnnotationConfigApplicationContext cxt = new AnnotationConfigApplicationContext(MyConfig.class);
 		this.resolver.setApplicationContext(cxt);
@@ -253,6 +252,22 @@ public void resolveExceptionWithAssertionError() throws Exception {
 		assertEquals(err.toString(), this.response.getContentAsString());
 	}
 
+	@Test
+	public void resolveExceptionWithAssertionErrorAsRootCause() throws Exception {
+		AnnotationConfigApplicationContext cxt = new AnnotationConfigApplicationContext(MyConfig.class);
+		this.resolver.setApplicationContext(cxt);
+		this.resolver.afterPropertiesSet();
+
+		AssertionError err = new AssertionError("argh");
+		FatalBeanException ex = new FatalBeanException("wrapped", err);
+		HandlerMethod handlerMethod = new HandlerMethod(new ResponseBodyController(), "handle");
+		ModelAndView mav = this.resolver.resolveException(this.request, this.response, handlerMethod, ex);
+
+		assertNotNull("Exception was not handled", mav);
+		assertTrue(mav.isEmpty());
+		assertEquals(err.toString(), this.response.getContentAsString());
+	}
+
 	@Test
 	public void resolveExceptionControllerAdviceHandler() throws Exception {
 		AnnotationConfigApplicationContext cxt = new AnnotationConfigApplicationContext(MyControllerAdviceConfig.class);