ReferenceCountedObject Class Reference
juce_core » memory

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

Inheritance diagram for ReferenceCountedObject:

## Public Member Functions

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

## Protected Member Functions

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

## 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

## Constructor & Destructor Documentation

## ReferenceCountedObject() [1/3]

ReferenceCountedObject::ReferenceCountedObject | ( |  | ) |

protected default

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

## ReferenceCountedObject() [2/3]

ReferenceCountedObject::ReferenceCountedObject | ( | const ReferenceCountedObject & |  | ) |

protected noexcept

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

## ReferenceCountedObject() [3/3]

ReferenceCountedObject::ReferenceCountedObject | ( | ReferenceCountedObject && |  | ) |

protected noexcept

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

## ~ReferenceCountedObject()

virtual ReferenceCountedObject::~ReferenceCountedObject | ( |  | ) |

protected virtual

Destructor.

References jassert.

## Member Function Documentation

## incReferenceCount()

void ReferenceCountedObject::incReferenceCount | ( |  | ) |

noexcept

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.

## decReferenceCount()

void ReferenceCountedObject::decReferenceCount | ( |  | ) |

noexcept

Decreases the object's reference count.

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

References jassert.

## decReferenceCountWithoutDeleting()

bool ReferenceCountedObject::decReferenceCountWithoutDeleting | ( |  | ) |

noexcept

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 ReferenceCountedObject::getReferenceCount | ( |  | ) | const

noexcept

Returns the object's current reference count.

## operator=() [1/2]

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

protected noexcept

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

## operator=() [2/2]

ReferenceCountedObject& ReferenceCountedObject::operator= | ( | ReferenceCountedObject && |  | ) |

protected noexcept

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

## resetReferenceCount()

void ReferenceCountedObject::resetReferenceCount | ( |  | ) |

protected noexcept

Resets the reference count to zero without deleting the object.

You should probably never need to use this!

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

- juce_ReferenceCountedObject.h

ReferenceCountedObject
A base class which provides methods for reference-counting.
Definition: juce_ReferenceCountedObject.h:66
ReferenceCountedObjectPtr
A smart-pointer class which points to a reference-counted object.
Definition: juce_ReferenceCountedObject.h:247