/**
 * Create a new session attributes handler. Session attribute names and types
 * are extracted from the {@code @SessionAttributes} annotation, if present,
 * on the given type.
 * @param handlerType the controller type
 */
public SessionAttributesHandler(Class<?> handlerType) {
	SessionAttributes ann = AnnotatedElementUtils.findMergedAnnotation(handlerType, SessionAttributes.class);
	if (ann != null) {
		Collections.addAll(this.attributeNames, ann.names());
		Collections.addAll(this.attributeTypes, ann.types());
	}
	this.knownAttributeNames.addAll(this.attributeNames);
}
 

/**
 * Create a new session attributes handler. Session attribute names and types
 * are extracted from the {@code @SessionAttributes} annotation, if present,
 * on the given type.
 * @param handlerType the controller type
 * @param sessionAttributeStore used for session access
 */
public SessionAttributesHandler(Class<?> handlerType, SessionAttributeStore sessionAttributeStore) {
	Assert.notNull(sessionAttributeStore, "SessionAttributeStore may not be null");
	this.sessionAttributeStore = sessionAttributeStore;

	SessionAttributes ann = AnnotatedElementUtils.findMergedAnnotation(handlerType, SessionAttributes.class);
	if (ann != null) {
		Collections.addAll(this.attributeNames, ann.names());
		Collections.addAll(this.attributeTypes, ann.types());
	}
	this.knownAttributeNames.addAll(this.attributeNames);
}
 

/**
 * Create a new session attributes handler. Session attribute names and types
 * are extracted from the {@code @SessionAttributes} annotation, if present,
 * on the given type.
 * @param handlerType the controller type
 */
public SessionAttributesHandler(Class<?> handlerType) {
	SessionAttributes ann = AnnotatedElementUtils.findMergedAnnotation(handlerType, SessionAttributes.class);
	if (ann != null) {
		Collections.addAll(this.attributeNames, ann.names());
		Collections.addAll(this.attributeTypes, ann.types());
	}
	this.knownAttributeNames.addAll(this.attributeNames);
}
 

/**
 * Create a new session attributes handler. Session attribute names and types
 * are extracted from the {@code @SessionAttributes} annotation, if present,
 * on the given type.
 * @param handlerType the controller type
 * @param sessionAttributeStore used for session access
 */
public SessionAttributesHandler(Class<?> handlerType, SessionAttributeStore sessionAttributeStore) {
	Assert.notNull(sessionAttributeStore, "SessionAttributeStore may not be null");
	this.sessionAttributeStore = sessionAttributeStore;

	SessionAttributes ann = AnnotatedElementUtils.findMergedAnnotation(handlerType, SessionAttributes.class);
	if (ann != null) {
		Collections.addAll(this.attributeNames, ann.names());
		Collections.addAll(this.attributeTypes, ann.types());
	}
	this.knownAttributeNames.addAll(this.attributeNames);
}
 

@Override
public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler)
		throws Exception {

	Class<?> clazz = ClassUtils.getUserClass(handler);
	Boolean annotatedWithSessionAttributes = this.sessionAnnotatedClassesCache.get(clazz);
	if (annotatedWithSessionAttributes == null) {
		annotatedWithSessionAttributes = (AnnotationUtils.findAnnotation(clazz, SessionAttributes.class) != null);
		this.sessionAnnotatedClassesCache.put(clazz, annotatedWithSessionAttributes);
	}

	if (annotatedWithSessionAttributes) {
		checkAndPrepare(request, response, this.cacheSecondsForSessionAttributeHandlers, true);
	}
	else {
		checkAndPrepare(request, response, true);
	}

	// Execute invokeHandlerMethod in synchronized block if required.
	if (this.synchronizeOnSession) {
		HttpSession session = request.getSession(false);
		if (session != null) {
			Object mutex = WebUtils.getSessionMutex(session);
			synchronized (mutex) {
				return invokeHandlerMethod(request, response, handler);
			}
		}
	}

	return invokeHandlerMethod(request, response, handler);
}
 

/**
 * Create a new instance for a controller type. Session attribute names and
 * types are extracted from the {@code @SessionAttributes} annotation, if
 * present, on the given type.
 * @param handlerType the controller type
 * @param sessionAttributeStore used for session access
 */
public SessionAttributesHandler(Class<?> handlerType, SessionAttributeStore sessionAttributeStore) {
	Assert.notNull(sessionAttributeStore, "SessionAttributeStore may not be null");
	this.sessionAttributeStore = sessionAttributeStore;

	SessionAttributes annotation =
			AnnotatedElementUtils.findMergedAnnotation(handlerType, SessionAttributes.class);
	if (annotation != null) {
		this.attributeNames.addAll(Arrays.asList(annotation.names()));
		this.attributeTypes.addAll(Arrays.asList(annotation.types()));
	}
	this.knownAttributeNames.addAll(this.attributeNames);
}
 

/**
 * Initialize a new HandlerMethodResolver for the specified handler type.
 * @param handlerType the handler class to introspect
 */
public void init(final Class<?> handlerType) {
	Set<Class<?>> handlerTypes = new LinkedHashSet<Class<?>>();
	Class<?> specificHandlerType = null;
	if (!Proxy.isProxyClass(handlerType)) {
		handlerTypes.add(handlerType);
		specificHandlerType = handlerType;
	}
	handlerTypes.addAll(Arrays.asList(handlerType.getInterfaces()));
	for (Class<?> currentHandlerType : handlerTypes) {
		final Class<?> targetClass = (specificHandlerType != null ? specificHandlerType : currentHandlerType);
		ReflectionUtils.doWithMethods(currentHandlerType, new ReflectionUtils.MethodCallback() {
			@Override
			public void doWith(Method method) {
				Method specificMethod = ClassUtils.getMostSpecificMethod(method, targetClass);
				Method bridgedMethod = BridgeMethodResolver.findBridgedMethod(specificMethod);
				if (isHandlerMethod(specificMethod) &&
						(bridgedMethod == specificMethod || !isHandlerMethod(bridgedMethod))) {
					handlerMethods.add(specificMethod);
				}
				else if (isInitBinderMethod(specificMethod) &&
						(bridgedMethod == specificMethod || !isInitBinderMethod(bridgedMethod))) {
					initBinderMethods.add(specificMethod);
				}
				else if (isModelAttributeMethod(specificMethod) &&
						(bridgedMethod == specificMethod || !isModelAttributeMethod(bridgedMethod))) {
					modelAttributeMethods.add(specificMethod);
				}
			}
		}, ReflectionUtils.USER_DECLARED_METHODS);
	}
	this.typeLevelMapping = AnnotationUtils.findAnnotation(handlerType, RequestMapping.class);
	SessionAttributes sessionAttributes = AnnotationUtils.findAnnotation(handlerType, SessionAttributes.class);
	this.sessionAttributesFound = (sessionAttributes != null);
	if (this.sessionAttributesFound) {
		this.sessionAttributeNames.addAll(Arrays.asList(sessionAttributes.names()));
		this.sessionAttributeTypes.addAll(Arrays.asList(sessionAttributes.types()));
	}
}
 

@Override
public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler)
		throws Exception {

	Class<?> clazz = ClassUtils.getUserClass(handler);
	Boolean annotatedWithSessionAttributes = this.sessionAnnotatedClassesCache.get(clazz);
	if (annotatedWithSessionAttributes == null) {
		annotatedWithSessionAttributes = (AnnotationUtils.findAnnotation(clazz, SessionAttributes.class) != null);
		this.sessionAnnotatedClassesCache.put(clazz, annotatedWithSessionAttributes);
	}

	if (annotatedWithSessionAttributes) {
		checkAndPrepare(request, response, this.cacheSecondsForSessionAttributeHandlers, true);
	}
	else {
		checkAndPrepare(request, response, true);
	}

	// Execute invokeHandlerMethod in synchronized block if required.
	if (this.synchronizeOnSession) {
		HttpSession session = request.getSession(false);
		if (session != null) {
			Object mutex = WebUtils.getSessionMutex(session);
			synchronized (mutex) {
				return invokeHandlerMethod(request, response, handler);
			}
		}
	}

	return invokeHandlerMethod(request, response, handler);
}
 

/**
 * Create a new instance for a controller type. Session attribute names and
 * types are extracted from the {@code @SessionAttributes} annotation, if
 * present, on the given type.
 * @param handlerType the controller type
 * @param sessionAttributeStore used for session access
 */
public SessionAttributesHandler(Class<?> handlerType, SessionAttributeStore sessionAttributeStore) {
	Assert.notNull(sessionAttributeStore, "SessionAttributeStore may not be null.");
	this.sessionAttributeStore = sessionAttributeStore;

	SessionAttributes annotation = AnnotationUtils.findAnnotation(handlerType, SessionAttributes.class);
	if (annotation != null) {
		this.attributeNames.addAll(Arrays.asList(annotation.names()));
		this.attributeTypes.addAll(Arrays.asList(annotation.types()));
	}

	for (String attributeName : this.attributeNames) {
		this.knownAttributeNames.add(attributeName);
	}
}
 

/**
 * Initialize a new HandlerMethodResolver for the specified handler type.
 * @param handlerType the handler class to introspect
 */
public void init(final Class<?> handlerType) {
	Set<Class<?>> handlerTypes = new LinkedHashSet<Class<?>>();
	Class<?> specificHandlerType = null;
	if (!Proxy.isProxyClass(handlerType)) {
		handlerTypes.add(handlerType);
		specificHandlerType = handlerType;
	}
	handlerTypes.addAll(Arrays.asList(handlerType.getInterfaces()));
	for (Class<?> currentHandlerType : handlerTypes) {
		final Class<?> targetClass = (specificHandlerType != null ? specificHandlerType : currentHandlerType);
		ReflectionUtils.doWithMethods(currentHandlerType, new ReflectionUtils.MethodCallback() {
			@Override
			public void doWith(Method method) {
				Method specificMethod = ClassUtils.getMostSpecificMethod(method, targetClass);
				Method bridgedMethod = BridgeMethodResolver.findBridgedMethod(specificMethod);
				if (isHandlerMethod(specificMethod) &&
						(bridgedMethod == specificMethod || !isHandlerMethod(bridgedMethod))) {
					handlerMethods.add(specificMethod);
				}
				else if (isInitBinderMethod(specificMethod) &&
						(bridgedMethod == specificMethod || !isInitBinderMethod(bridgedMethod))) {
					initBinderMethods.add(specificMethod);
				}
				else if (isModelAttributeMethod(specificMethod) &&
						(bridgedMethod == specificMethod || !isModelAttributeMethod(bridgedMethod))) {
					modelAttributeMethods.add(specificMethod);
				}
			}
		}, ReflectionUtils.USER_DECLARED_METHODS);
	}
	this.typeLevelMapping = AnnotationUtils.findAnnotation(handlerType, RequestMapping.class);
	SessionAttributes sessionAttributes = AnnotationUtils.findAnnotation(handlerType, SessionAttributes.class);
	this.sessionAttributesFound = (sessionAttributes != null);
	if (this.sessionAttributesFound) {
		this.sessionAttributeNames.addAll(Arrays.asList(sessionAttributes.names()));
		this.sessionAttributeTypes.addAll(Arrays.asList(sessionAttributes.types()));
	}
}
 

/**
 * {@inheritDoc}
 */
static String[] findSessionAttributeNames(Class<?> controllerClass) {
    SessionAttributes attrs = AnnotationUtils.findAnnotation(controllerClass, SessionAttributes.class);
    if (attrs != null) {
      return attrs.value();
    }
    return null;
}
 

/**
 * {@inheritDoc}
 */
static Class<?>[] findSessionAttributeTypes(Class<?> controllerClass) {
    SessionAttributes attrs = AnnotationUtils.findAnnotation(controllerClass, SessionAttributes.class);
    if (attrs != null) {
      return attrs.types();
    }
    return null;
}