fix to class check for nil

convenience functions
init functions

MVMCore/MVMCore/ActionHandling/MVMCoreActionHandler.m

@@ -36,8 +36,7 @@ NSString * const KeyActionTypeOpen = @"openPage";
 @implementation MVMCoreActionHandler
 
 + (nullable instancetype)sharedActionHandler {
-    [MVMCoreActionUtility classIsInstanceTypeOfClass:[MVMCoreObject sharedInstance].actionHandler.class otherClass:self throwException:YES];
-    return [MVMCoreObject sharedInstance].actionHandler;
+    return [MVMCoreActionUtility initializerClassCheck:[MVMCoreObject sharedInstance].actionHandler classToVerify:self];
 }
 
 - (void)handleActionWithDictionary:(nullable NSDictionary *)dictionary additionalData:(nullable NSDictionary *)additionalData delegate:(nullable NSObject <MVMCoreLoadDelegateProtocol, MVMCorePresentationDelegateProtocol,MVMCoreActionDelegateProtocol>*)delegate {

MVMCore/MVMCore/OtherHandlers/MVMCoreCache.m

@@ -42,8 +42,7 @@
 static NSString * const STATIC_CACHE_COMPONENT = @"StaticCache.txt";
 
 + (nullable instancetype)sharedCache {
-    [MVMCoreActionUtility classIsInstanceTypeOfClass:[MVMCoreObject sharedInstance].cache.class otherClass:self throwException:YES];
-    return [MVMCoreObject sharedInstance].cache;
+    return [MVMCoreActionUtility initializerClassCheck:[MVMCoreObject sharedInstance].cache classToVerify:self];
 }
 
 - (nullable instancetype)init {

MVMCore/MVMCore/OtherHandlers/MVMCoreLoggingHandler.m

@@ -13,7 +13,7 @@
 @implementation MVMCoreLoggingHandler
 
 + (nullable instancetype)sharedLoggingHandler {
-    if ([MVMCoreActionUtility classIsInstanceTypeOfClass:[MVMCoreObject sharedInstance].loggingDelegate.class otherClass:self throwException:NO]) {
+    if ([MVMCoreObject sharedInstance].loggingDelegate && [MVMCoreActionUtility classIsInstanceTypeOfClass:[MVMCoreObject sharedInstance].loggingDelegate.class otherClass:self throwException:NO]) {
         return (MVMCoreLoggingHandler *)[MVMCoreObject sharedInstance].loggingDelegate;
     } else {
         return nil;

MVMCore/MVMCore/Session/MVMCoreSessionObject.m

@@ -13,8 +13,7 @@
 @implementation MVMCoreSessionObject
 
 + (nullable instancetype)sharedGlobal {
-    [MVMCoreActionUtility classIsInstanceTypeOfClass:[MVMCoreObject sharedInstance].session.class otherClass:self throwException:YES];
-    return [MVMCoreObject sharedInstance].session;
+    return [MVMCoreActionUtility initializerClassCheck:[MVMCoreObject sharedInstance].session classToVerify:self];
 }
 
 - (nullable NSDictionary *)getInitialParameters {

MVMCore/MVMCore/Session/MVMCoreSessionTimeHandler.m

@@ -47,8 +47,7 @@
 @implementation MVMCoreSessionTimeHandler
 
 + (nullable instancetype)sharedSessionHandler {
-    [MVMCoreActionUtility classIsInstanceTypeOfClass:[MVMCoreObject sharedInstance].sessionHandler.class otherClass:self throwException:YES];
-    return [MVMCoreObject sharedInstance].sessionHandler;
+    return [MVMCoreActionUtility initializerClassCheck:[MVMCoreObject sharedInstance].sessionHandler classToVerify:self];
 }
 
 - (instancetype)init {

MVMCore/MVMCore/Utility/Helpers/MVMCoreActionUtility.h

@@ -26,4 +26,7 @@
 // returns if the class is not the same or a subclass of the other class. Can pass throw an exception as well
 + (BOOL)classIsInstanceTypeOfClass:(Class)theClass otherClass:(Class)otherClass throwException:(BOOL)throwException;
 
+// Calls the above function with throw exception yes if the object is not nil. Returns the object. Convenience function for one liner in initializer.
++ (id)initializerClassCheck:(nullable NSObject *)object classToVerify:(Class)classToVerify;
+
 @end

MVMCore/MVMCore/Utility/Helpers/MVMCoreActionUtility.m

@@ -147,4 +147,11 @@
     return YES;
 }
 
++ (id)initializerClassCheck:(nullable NSObject *)object classToVerify:(Class)classToVerify {
+    if (object) {
+        [self classIsInstanceTypeOfClass:object.class otherClass:classToVerify throwException:YES];
+    }
+    return object;
+}
+
 @end

MVMCore/MVMCore/ViewControllerMapping/MVMCoreViewControllerMappingObject.m

@@ -27,8 +27,7 @@
 @implementation MVMCoreViewControllerMappingObject
 
 + (nullable instancetype)sharedViewControllerMappingObject {
-    [MVMCoreActionUtility classIsInstanceTypeOfClass:[MVMCoreObject sharedInstance].viewControllerMapping.class otherClass:self throwException:YES];
-    return [MVMCoreObject sharedInstance].viewControllerMapping;
+    return [MVMCoreActionUtility initializerClassCheck:[MVMCoreObject sharedInstance].viewControllerMapping classToVerify:self];
 }
 
 #pragma mark - View Controller Mapping