juce::ReferenceCountedObject Class Reference

A base class which provides methods for reference-counting. More...

#include <juce_ReferenceCountedObject.h>

Inheritance diagram for juce::ReferenceCountedObject:

Collaboration diagram for juce::ReferenceCountedObject:

Public Member Functions
void	decReferenceCount () noexcept
	Decreases the object's reference count.
bool	decReferenceCountWithoutDeleting () noexcept
	Decreases the object's reference count.
int	getReferenceCount () const noexcept
	Returns the object's current reference count.
void	incReferenceCount () noexcept
	Increments the object's reference count.

Protected Member Functions
	ReferenceCountedObject ()=default
	Creates the reference-counted object (with an initial ref count of zero).
	ReferenceCountedObject (const ReferenceCountedObject &) noexcept
	Copying from another object does not affect this one's reference-count.
	ReferenceCountedObject (ReferenceCountedObject &&) noexcept
	Copying from another object does not affect this one's reference-count.
virtual	~ReferenceCountedObject ()
	Destructor.
ReferenceCountedObject &	operator= (const ReferenceCountedObject &) noexcept
	Copying from another object does not affect this one's reference-count.
ReferenceCountedObject &	operator= (ReferenceCountedObject &&) noexcept
	Copying from another object does not affect this one's reference-count.
void	resetReferenceCount () noexcept
	Resets the reference count to zero without deleting the object.

Private Attributes
Atomic< int >	refCount { 0 }

Friends
struct	ContainerDeletePolicy< ReferenceCountedObject >

Detailed Description

A base class which provides methods for reference-counting.

To add reference-counting to a class, derive it from this class, and use the ReferenceCountedObjectPtr class to point to it.

e.g.

class MyClass : public ReferenceCountedObject
{
    void foo();
 
    // This is a neat way of declaring a typedef for a pointer class,
    // rather than typing out the full templated name each time..
    using Ptr = ReferenceCountedObjectPtr<MyClass>;
};
 
MyClass::Ptr p = new MyClass();
MyClass::Ptr p2 = p;
p = nullptr;
p2->foo();

Once a new ReferenceCountedObject has been assigned to a pointer, be careful not to delete the object manually.

This class uses an Atomic<int> value to hold the reference count, so the reference count can be updated on multiple threads. Note that whilst it's thread-safe to create and delete a ReferenceCountedObjectPtr to a ReferenceCountedObject shared between threads, it's not thread-safe to modify or swap the ReferenceCountedObject.

For a faster but non-thread-safe version, use SingleThreadedReferenceCountedObject instead.

See also

ReferenceCountedObjectPtr, ReferenceCountedArray, SingleThreadedReferenceCountedObject

@tags{Core}

Constructor & Destructor Documentation

ReferenceCountedObject() [1/3]

juce::ReferenceCountedObject::ReferenceCountedObject ( )

protecteddefault

Creates the reference-counted object (with an initial ref count of zero).

ReferenceCountedObject() [2/3]

juce::ReferenceCountedObject::ReferenceCountedObject ( const ReferenceCountedObject &  )

inlineprotectednoexcept

Copying from another object does not affect this one's reference-count.

ReferenceCountedObject() [3/3]

juce::ReferenceCountedObject::ReferenceCountedObject ( ReferenceCountedObject &&  )

inlineprotectednoexcept

Copying from another object does not affect this one's reference-count.

~ReferenceCountedObject()

virtual juce::ReferenceCountedObject::~ReferenceCountedObject ( )

inlineprotectedvirtual

Destructor.

References jassert.

Member Function Documentation

decReferenceCount()

void juce::ReferenceCountedObject::decReferenceCount ( )

inlinenoexcept

Decreases the object's reference count.

If the count gets to zero, the object will be deleted.

References jassert.

decReferenceCountWithoutDeleting()

bool juce::ReferenceCountedObject::decReferenceCountWithoutDeleting ( )

inlinenoexcept

Decreases the object's reference count.

If the count gets to zero, the object will not be deleted, but this method will return true, allowing the caller to take care of deletion.

References jassert.

getReferenceCount()

int juce::ReferenceCountedObject::getReferenceCount ( ) const

inlinenoexcept

Returns the object's current reference count.

incReferenceCount()

void juce::ReferenceCountedObject::incReferenceCount ( )

inlinenoexcept

Increments the object's reference count.

This is done automatically by the smart pointer, but is public just in case it's needed for nefarious purposes.

operator=() [1/2]

ReferenceCountedObject & juce::ReferenceCountedObject::operator= ( const ReferenceCountedObject &  )

inlineprotectednoexcept

Copying from another object does not affect this one's reference-count.

operator=() [2/2]

ReferenceCountedObject & juce::ReferenceCountedObject::operator= ( ReferenceCountedObject &&  )

inlineprotectednoexcept

Copying from another object does not affect this one's reference-count.

resetReferenceCount()

void juce::ReferenceCountedObject::resetReferenceCount ( )

inlineprotectednoexcept

Resets the reference count to zero without deleting the object.

You should probably never need to use this!

Friends And Related Symbol Documentation

ContainerDeletePolicy< ReferenceCountedObject >

friend struct ContainerDeletePolicy< ReferenceCountedObject >

friend

Member Data Documentation

refCount

Atomic<int> juce::ReferenceCountedObject::refCount { 0 }

private

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

• juce_ReferenceCountedObject.h