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  3. UClass

UClass

An object class.

Unreal Engine C++ API Reference > Runtime > CoreUObject > UObject

Inheritance Hierarchy

References

   
Module CoreUObject
Header /Engine/Source/Runtime/CoreUObject/Public/UObject/Class.h
Include #include "UObject/Class.h"

Syntax

class UClass : public UStruct

Remarks

An object class.

Variables

  Type Name Description
Public variable bool bCooked Used to check if the class was cooked or not
Public variable bool bLayoutChanging Used to check if the class layout is currently changing and therefore is not ready for a CDO to be created
Public variable EClassCastFlags ClassCastFlags Cast flags used to accelerate dynamic_cast on objects of this type for common T
Public variable FName ClassConfigName Which Name.ini file to load Config variables out of
Public variable ClassConstructorType ClassConstructor  
Public variable TObjectPtr< UObject > ClassDefaultObject The class default object; used for delta serialization and object initialization
Public variable EClassFlags ClassFlags Class flags; See EClassFlags for more information
Public variable TObjectPtr< UObject > ClassGeneratedBy This is the blueprint that caused the generation of this class, or null if it is a native compiled-in class
Public variable TArray< FRepRecord > ClassReps List of replication records
Public variable int32 ClassUnique Class pseudo-unique counter; used to accelerate unique instance name generation
Public variable ClassVTableHelperCtorCallerType ClassVTableHelperCtorCaller  
Public variable TObjectPtr< UClass > ClassWithin The required type for the outer of instances of this class
Public variable FUObjectCppClassStaticFunctions CppClassStaticFunctions  
Public variable int32 FirstOwnedClassRep Index of the first ClassRep that belongs to this class.
Public variable TArray< FImplementedInterface > Interfaces The list of interfaces which this class implements, along with the pointer property that is located at the offset of the interface's vtable.
Public variable TArray< FNativeFunctionLookup > NativeFunctionLookupTable This class's native functions.
Public variable TArray< UField * > NetFields List of network relevant fields (functions)
Public variable FField * PropertiesPendingDestruction Linked list of properties to be destroyed when this class is destroyed that couldn't be destroyed in PurgeClass
Public variable UE::GC::FSchemaOwner ReferenceSchema GC schema, finalized in AssembleReferenceTokenStream
Protected variable void * SparseClassData This is where we store the data that is only changed per class instead of per instance
Protected variable TObjectPtr< UScriptStruct > SparseClassDataStruct The struct used to store sparse class data.

Constructors

  Type Name Description
Public function  

UClass ( FVTableHelper& Helper
)

 DO NOT USE. This constructor is for internal usage only for hot-reload purposes.
Public function  

UClass ( const FObjectInitializer& ObjectInitializer
)

 Constructors.
Public function  

UClass ( const FObjectInitializer& ObjectInitializer,
UClass* InSuperClass
)

 Create a new UClass given its superclass.
Public function  

UClass ( EStaticConstructor,
FName InName,
uint32 InSize,
uint32 InAlignment,
EClassFlags InClassFlags,
EClassCastFlags InClassCastFlags,
const TCHAR* InClassConfigName,
EObjectFlags InFlags,
ClassConstructorType InClassConstructor,
ClassVTableHelperCtorCallerType InClassVTableHelperCtorCaller,
FUObjectCppClassStaticFunctions&& InCppClassStaticFunctions
)

 Called when statically linked.

Destructors

  Type Name Description
Public function  

~UClass ()

 Destructor.

Functions

  Type Name Description
Public function Static void  
Public function Static UObject *  
Public function void

AddDefaultSubobject ( UObject* NewSubobject,
const UClass* BaseClass
)

 Adds a new default instance map item
Public function void

AddFunctionToFunctionMap ( UFunction* Function,
FName FuncName
)

 Add a function to the function map
Public function void

AddNativeFunction ( const WIDECHAR* InName,
FNativeFuncPtr InPointer
)

 Add a native function to the internal native function table, but with a unicode name.
Public function void

AddNativeFunction ( const ANSICHAR* InName,
FNativeFuncPtr InPointer
)

 Add a native function to the internal native function table
Public function Static void Callback used to allow an object to register its direct object references that are not already covered by the token stream.
Public function void Assembles the token stream for realtime garbage collection by combining the per class only token stream for each class in the class hierarchy.
Public function Static void Assemble reference token streams for all classes if they haven't had it assembled already
Public function Const void Calls AddReferencedObjects static method on the specified object.
Public function Const void Calls the c++ class's AppendToClassSchema static function
Public function Const void Calls the c++ class's DeclareConstructClasses static function (from the nearest native parent if this is not native)
Public function Const void Calls the c++ class's DeclareCustomVersions static function (from the nearest native parent if this is not native)
Public function Virtual Const bool Some classes may not support creating assets of their type
Public function Virtual Const UE_INTERNAL bool Returns true if an InstanceDataObject be created from an instance of this type.
Protected function void  
Public function void Clears the function name caches, in case things have changed
Public function void

ClearSparseClassDataStruct ( bool bInRecomplingOnLoad
)

 Clears the sparse class data struct for this and all child classes that directly reference it as a super-struct This will rename the current sparse class data struct aside into the transient package
Public function Virtual void Conditionally recompiles the class after loading, in case any dependencies were also newly loaded
Public function Static FString Takes a FullName (from e.g. AssetData.GetFullName or UObject.GetFullName) in either ShortTypeFullName or PathFullName form ShortTypeFullName: "ClassObjectName /PackagePath/PackageShortName.ObjectName:SubObjectName" PathFullName: "/ClassPath/ClassPackage.ClassObjectName /PackagePath/PackageShortName.ObjectName:SubObjectName" Converts it to ShortTypeFullName if not already in that format and returns it
Public function Static FString

ConvertPathNameToShortTypeName ( FStringView InClassPathOrShortTypeName
)

 Returns the ObjectName portion of a ClassPath name: "/Path/To.Object" is converted to "Object".
Protected function Virtual UObject * Get the default object from the class, creating it if missing, if requested or under a few other circumstances
Public function void  
Public function Virtual Const void

CreatePersistentUberGraphFrame ( UObject* Obj,
bool bCreateOnlyIfEmpty,
bool bSkipSuperClass,
UClass* OldClass
)

 Creates memory to store temporary data
Protected function void *  
Public function Virtual Const void

DestroyPersistentUberGraphFrame ( UObject* Obj,
bool bSkipSuperClass
)

 Clears memory to store temporary data
Public function void Destroys properties that couldn't be destroyed in PurgeClass
Public function Virtual Const UObject *

FindArchetype ( const UClass* ArchetypeClass,
const FName ArchetypeName
)

 Finds the object that is used as the parent object when serializing properties, overridden for blueprints
Public function Static UClass *

FindCommonBase ( const TArray< UClass* >& InClasses
)

 Finds the common base class that parents the array of classes passed in.
Public function Static UClass *

FindCommonBase ( UClass* InClassA,
UClass* InClassB
)

 Finds the common base class that parents the two classes passed in.
Public function Const UFunction * Looks for a given function name
Public function Virtual void  
Public function Const void

GenerateFunctionList ( TArray< FName >& OutArray
)

  
Public function Virtual Const UObject * Returns archetype object for CDO
Public function Const const void * Returns archetype for sparse class data
Public function Const const UClass *  
Public function Virtual UClass * If there are potentially multiple versions of this class (e.g. blueprint generated classes), this function will return the authoritative version, which should be used for references
Public function Const void

GetAutoCollapseCategories ( TArray< FString >& OutAutoCollapseCategories
)

  
Public function Const void

GetAutoExpandCategories ( TArray< FString >& OutAutoExpandCategories
)

  
Public function Const EClassFlags Gets the class flags.
Public function Const void

GetClassGroupNames ( TArray< FString >& OutClassGroupNames
)

  
Public function Const FTopLevelAssetPath Returns class path name as a package + class FName pair
Public function Const const FString Translates the hardcoded script config names (engine, editor, input and game) to their global pendants and otherwise uses config(myini) name to look for a game specific implementation and creates one based on the default if it doesn't exist yet.
Public function Const const ICppClassTypeInfo * Provides access to C++ type info.
Public function Const T * Get the default object from the class and cast to a particular type
Public function Const UObject *

GetDefaultObject ( bool bCreateIfNeeded
)

 Get the default object from the class
Public function Const FName Get the name of the CDO for the this class
Public function Virtual void Returns all objects that should be preloaded before the class default object is serialized at load time.
Public function void

GetDefaultObjectSubobjects ( TArray< UObject* >& OutDefaultSubobjects
)

 Gets all default instanced objects (often components).
Public function Static FFeedbackContext & Feedback context for default property import
Public function int32 Returns amount of memory used by default object
Public function UObject * Searches for the default instanced object (often a component) by name
Public function Const FString  
Public function Const void

GetHideFunctions ( TArray< FString >& OutHideFunctions
)

 Editor only properties.
Public function void * Returns a pointer to the sidecar data structure.
Public function Const UPackage *  
Public function Virtual Const uint8 * Returns memory used to store temporary data on an instance, used by blueprints
Public function Const void

GetPrioritizeCategories ( TArray< FString >& OutPrioritizedCategories
)

  
Public function Const FTopLevelAssetPath If this class was recompiled, returns the path to where we should find the new (i.e. reinstanced) class.
Protected function Virtual Const FTopLevelAssetPath Internal helper method for GetReinstancedClassPathName().
Public function const void * Returns a pointer to the sidecar data structure, based on the EGetSparseClassDataMethod.
Public function Const UScriptStruct * Returns the struct used by the sparse class data archetype
Public function Const UScriptStruct * Returns a pointer to the type of the sidecar data structure if one is specified.
Public function Const UClass * Returns parent class, the parent of a Class is always another class
Public function Const bool

HasAllCastFlags ( EClassCastFlags FlagsToCheck
)

  
Public function Const bool

HasAllClassFlags ( EClassFlags FlagsToCheck
)

 Used to safely check whether all of the passed in flags are set.
Public function Const bool Used to safely check whether the passed in flag is set.
Public function Const bool

HasAnyClassFlags ( EClassFlags FlagsToCheck
)

 Used to safely check whether the passed in flag is set.
Public function Virtual Const bool

HasProperty ( const FProperty* InProperty
)

 Checks if the property exists on this class or a parent class.
Public function Const bool

ImplementsInterface ( const UClass* SomeInterface
)

 This will return whether or not this class implements the passed in class / interface
Public function Virtual void

InitPropertiesFromCustomList ( uint8* DataPtr,
const uint8* DefaultDataPtr
)

 Helper method to assist with initializing object properties from an explicit list.
Public function Const bool

IsAutoCollapseCategory ( const TCHAR* InCategory
)

  
Public function Const bool

IsAutoExpandCategory ( const TCHAR* InCategory
)

  
Public function Const bool

IsClassGroupName ( const TCHAR* InGroupName
)

  
Public function Const bool

IsFunctionHidden ( const TCHAR* InFunction
)

  
Public function Virtual Const bool Determines if the specified function has been implemented in a Blueprint
Public function Const bool

IsPrioritizeCategory ( const TCHAR* InCategory
)

  
Public function Static bool Helper function for determining if the given class is compatible with structured archive serialization
Public function Static bool

IsShortTypeName ( FStringView ClassPathOrShortTypeName
)

 Returns whether the given stringview is in ShortTypeName form: No directory separators "/" or object separators ".", SUBOBJECT_DELIMITER Returns true for empty string.
Public function Const bool Returns whether the sparse class data on this instance overrides that of its archetype (in type or value)
Public function Virtual void

PostInitInstance ( UObject* InObj,
FObjectInstancingGraph* InstanceGraph
)

 Called after PostInitProperties during object construction to allow class specific initialization of an object instance.
Public function Virtual void Wraps the PostLoad() call for the class default object.
Public function Virtual void Called during PostLoad of an object to allow class specific PostLoad operations of an object instance.
Public function Virtual void

PurgeClass ( bool bRecompilingOnLoad
)

 Purges out the properties of this class in preparation for it to be regenerated
Public function void Remove a function from the function map
Public function Virtual void Serializes the passed in object as this class's default object using the given archive
Public function Virtual void Serializes the passed in object as this class's default object using the given archive slot
Public function void Serializes the associated sparse class data for the passed in object using the given archive slot.
Public function void

SetCppTypeInfoStatic ( const FCppClassTypeInfoStatic* InCppTypeInfoStatic
)

 Sets C++ type information. Should not be NULL.
Public function void

SetSparseClassDataStruct ( UScriptStruct* InSparseClassDataStruct
)

  
Public function Virtual Const void Allows class to provide data to the object initializer that can affect how native class subobjects are created.
Public function void Initializes the ClassReps and NetFields arrays used by replication.
Public function Static UClass * Returns a UClass object representing this class at runtime
Public function Static EClassCastFlags Returns the static cast flags for this class
Public function Static const TCHAR * Returns the package this class belongs in
Public function Static void  
Public function Static FTopLevelAssetPath

TryConvertShortTypeNameToPathName ( const FString& InShortTypeName,
ELogVerbosity::Type AmbiguousMessageVerbosity,
const TCHAR* AmbiguousClassMessage
)

 Tries to convert short class name to class path name.
Public function Static FTopLevelAssetPath

TryConvertShortTypeNameToPathName ( UClass* TypeClass,
const FString& InShortTypeName,
ELogVerbosity::Type AmbiguousMessageVerbosity,
const TCHAR* AmbiguousClassMessage
)

 Tries to convert short class name to class path name.
Public function Static T *

TryFindTypeSlow ( const FString& InShortNameOrPathName,
EFindFirstObjectOptions InOptions
)

 Utility function that tries to find a type (class/struct/enum) given a path name or a short name however it will throw a warning (with a callstack) if it's the latter.
Public function Static UField *

TryFindTypeSlow ( UClass* TypeClass,
const FString& InPathNameOrShortName,
EFindFirstObjectOptions InOptions
)

 Utility function that tries to find a type (class/struct/enum) given a path name or a short name however it will throw a warning (with a callstack) if it's the latter.
Public function Static T *

TryFindTypeSlowSafe ( const FString& InShortNameOrPathName,
EFindFirstObjectOptions InOptions
)

 Utility function that tries to find a type (class/struct/enum) given a path name or a short name however it will throw a warning (with a callstack) if it's the latter.
Public function Static UField *

TryFindTypeSlowSafe ( UClass* TypeClass,
const FString& InPathNameOrShortName,
EFindFirstObjectOptions InOptions
)

 Utility function that tries to find a type (class/struct/enum) given a path name or a short name however it will throw a warning (with a callstack) if it's the latter.
Public function Static bool

TryFixShortClassNameExportPath ( FString& InOutExportPathToFix,
ELogVerbosity::Type AmbiguousMessageVerbosity,
const TCHAR* AmbiguousClassMessage,
bool bClearOnError
)

 Tries to fix an export path containing short class name.

Overridden from UStruct

  Type Name Description
Public function Virtual Const const TCHAR * Returns the struct/ class prefix used for the C++ declaration of this struct/ class.
Public function Virtual Const bool If true, this class has been cleaned and sanitized (trashed) and should not be used
Public function Virtual void

Link ( FArchive& Ar,
bool bRelinkExistingProperties
)

 Creates the field/property links and gets structure ready for use at runtime
Public function Virtual void

SetSuperStruct ( UStruct* NewSuperStruct
)

 Sets the super struct pointer and updates hash information as necessary.

Overridden from UField

  Type Name Description
Public function Virtual void

Bind ()

 Find the class's native constructor.

Overridden from UObject

  Type Name Description
Public function Virtual void Called to finish destroying the object.
Public function Virtual Const void  
Public function Virtual Const void Gathers a list of asset registry searchable tags which are name/value pairs with some type information This only needs to be implemented for asset objects
Public function Virtual FString

GetDesc ()

 Return a one line description of an object for viewing in the thumbnail view of the generic browser
Public function Virtual void Called during cooking.
Public function Virtual FRestoreForUObjectOverwrite * Save information for StaticAllocateObject in the case of overwriting an existing object.
Public function Virtual Const bool

IsAsset ()

 Returns true if this object is considered an asset.
Public function Virtual Const bool IsNameStableForNetworking means an object can be referred to its path name (relative to outer) over the network
Public function Virtual void Called after the C++ constructor and after the properties have been initialized, including those loaded from config.
Public function Virtual void Do any object-specific cleanup required immediately after loading an object.
Public function Virtual bool

Rename ( const TCHAR* NewName,
UObject* NewOuter,
ERenameFlags Flags
)

 Rename this object to a unique name, or change its outer.
Public function Virtual void Handles reading, writing, and reference collecting using FArchive.
Public function Virtual void Tags objects that are part of the same asset with the specified object flag, used for GC checking
Protected function Virtual Const void

ThreadedPostLoadAssetRegistryTagsOverride ( FPostLoadAssetRegistryTagsContext& Context
)

 Performs fixup on loaded asset registry data.

Overridden from UObjectBase

  Type Name Description
Public function Virtual void

DeferredRegister ( UClass* UClassStaticClass,
const TCHAR* PackageName,
const TCHAR* Name
)

 Convert a boot-strap registered class into a real one, add to uobject array, etc

Operators

  Type Name Description
Public function void

operator delete ( void* InMem
)

 Eliminate V1062 warning from PVS-Studio while keeping MSVC and Clang happy.
Public function void *

operator new ( const size_t InSize,
EInternal InInternalOnly,
UObject* InOuter,
FName InName,
EObjectFlags InSetFlags
)

 For internal use only; use StaticConstructObject() to create new objects.
Public function void *

operator new ( const size_t InSize,
EInternal* InMem
)

 For internal use only; use StaticConstructObject() to create new objects.

Typedefs

Name Description
ClassConstructorType  
ClassVTableHelperCtorCallerType  
StaticClassFunctionType  
Super Typedef for the base class (UStruct)
ThisClass Typedef for UClass.
WithinClass The required type of this object's outer (class UPackage)

Constants

Name Description
StaticClassFlags Bitwise union of EClassFlags pertaining to this class.

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