Arp::Singleton< Derived > Class Template Reference

This class implements the singleton pattern. More...

#include <Singleton.hxx>

Static Public Member Functions
template<class T = Instance, class ... Args>
static Instance &	CreateInstance (Args &&... args)
	Creates this singleton instance. More...
static bool	IsCreated (void)
	Determines if this singleton instance is create yet. More...
static Instance &	GetInstance (void)
	Gets a reference of the singleton instance. More...
static Instance *	GetInstancePtr (void)
	Gets a pointer to the singleton instance. More...
static void	DisposeInstance (void)
	Disposes this singleton instance. More...

Protected Types
typedef Singleton< Derived >	SingletonBase
	Defines this type to be used from derived classes.

Protected Member Functions
	Singleton (void)=default
	The protected default constructor.
	~Singleton (void)=default
	The protected default destructor.

Static Protected Member Functions
static void	SetInstance (Instance *pOther)
	Sets the singleton instance. More...
static void	AssignInstanceFrom (Instance &other)
	Assigns the singleton instance from another singleton instance of the same type. More...

Detailed Description

template<class Derived>
class Arp::Singleton< Derived >

This class implements the singleton pattern.

Template Parameters

Derived

The class to apply the singleton pattern to.

Derive your own class called MyClass from Singleton<MyClass> to apply the singleton pattern to this class.

This class uses CRTP (Curiously recurring template pattern) to implement an own singleton instance for each derived class. For CRTP see: https://en.wikipedia.org/wiki/Curiously_recurring_template_pattern

Member Function Documentation

AssignInstanceFrom()

template<class Derived >

void Arp::Singleton< Derived >::AssignInstanceFrom ( Instance &  other )

inlinestaticprotected

Assigns the singleton instance from another singleton instance of the same type.

Parameters

other

The singleton instance to assign to this instance.

For internal use only.

This operation is used to distribute a singleton from one dynamic shared libraray to another, all providing their own set of static variables.

CreateInstance()

template<class Derived >

template<class T , class ... Args>

Singleton< Derived >::Instance & Arp::Singleton< Derived >::CreateInstance ( Args &&...  args )

inlinestatic

Creates this singleton instance.

Parameters

args	The arguments passed to the constructor of T. Thus there must exists a constructor with a matching signature.

Returns

The new created singleton instance.

Template Parameters

T	The type to create. Usually this is the derived type, but it might also be a polymorphic type.
Args	The argument list must comply to a constructor with a matching signature.

DisposeInstance()

template<class Derived >

void Arp::Singleton< Derived >::DisposeInstance ( void  )

inlinestatic

Disposes this singleton instance.

Deletes the singleton instance pointer.

GetInstance()

template<class Derived >

Derived & Arp::Singleton< Derived >::GetInstance ( void  )

inlinestatic

Gets a reference of the singleton instance.

Returns

The singleton instance as reference.

Exceptions

Exception

If the singleton instance was not created yet.

GetInstancePtr()

template<class Derived >

Derived * Arp::Singleton< Derived >::GetInstancePtr ( void  )

inlinestatic

Gets a pointer to the singleton instance.

Returns

The singleton instance as pointer, if it was created yet, otherwise nullptr.

IsCreated()

template<class Derived >

bool Arp::Singleton< Derived >::IsCreated ( void  )

inlinestatic

Determines if this singleton instance is create yet.

Returns

true if this singleton was created yet, otherwise false.

SetInstance()

template<class Derived >

void Arp::Singleton< Derived >::SetInstance ( Instance *  pOther )

inlinestaticprotected

Sets the singleton instance.

Parameters

pOther

The singleton instance to assign to this instance.

For internal use only.

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The documentation for this class was generated from the following file:

• Arp/System/Core/Singleton.hxx