itk::ObjectStore< TObjectType > Class Template Reference

#include <itkObjectStore.h>

Inheritance diagram for itk::ObjectStore< TObjectType >:

Collaboration diagram for itk::ObjectStore< TObjectType >:

Detailed Description

template<class TObjectType>
class itk::ObjectStore< TObjectType >

A specialized memory management object for allocating and destroying contiguous blocks of objects.

ObjectStore implements a dynamically sizeable free memory store, from which instantiated objects can be borrowed and returned without always invoking calls to new/delete. This type of memory management is useful in situations where calls to new/delete may be expensive, such as a multithreaded environment to avoid the heap contention problem.

ObjectStore is designed to grow dynamically. Shrinking is a more difficult problem and is only done if it will not invalidate any pointers that have been "lent" to a calling application.

This implementation uses a very simple, list-based scheme to manage pointers that have been borrowed and returned. Memory overhead incurred is one pointer per object allocated. Because of this overhead, ObjectStore is not efficient for use with small objects such as native types.

Important notes on thread-safety: This object is thread-safe in the same sense that STL defines thread-safety: simultaneous operations on distinct containers are safe. It is the user's responsibility to apply appropriate mutex locks if the same container is used across multiple threads. One (or more) ObjectStore's can be safely be created for each thread – and may even be more efficient in terms of memory use than sharing a single ObjectStore across threads. Calls to new and delete have been placed in critical sections in case a compiler's implementation of new/delete is not thread-safe.

Warning

For efficiency reasons, the ObjectStore does not guard against the same pointer being Returned() more than once. Doing this could result in serious problems.

Definition at line 63 of file itkObjectStore.h.

Classes
struct	MemoryBlock

Public Types
typedef SmartPointer< const Self >	ConstPointer
typedef std::vector< ObjectType * >	FreeListType
enum	GrowthStrategyType {   LINEAR_GROWTH = 0,   EXPONENTIAL_GROWTH = 1 }
typedef TObjectType	ObjectType
typedef SmartPointer< Self >	Pointer
typedef ObjectStore	Self
typedef Object	Superclass
Public Types inherited from itk::Object
typedef SmartPointer< const Self >	ConstPointer
typedef SmartPointer< Self >	Pointer
typedef Object	Self
typedef LightObject	Superclass
Public Types inherited from itk::LightObject
typedef SmartPointer< const Self >	ConstPointer
typedef SmartPointer< Self >	Pointer
typedef LightObject	Self

Public Member Functions
ObjectType *	Borrow ()
void	Clear ()
virtual ::itk::LightObject::Pointer	CreateAnother (void) const
virtual const char *	GetNameOfClass () const
virtual SizeValueType	GetSize () const
void	Reserve (SizeValueType n)
void	Return (ObjectType *p)
void	SetGrowthStrategyToExponential ()
void	SetGrowthStrategyToLinear ()
void	Squeeze ()
virtual void	SetLinearGrowthSize (SizeValueType _arg)
virtual SizeValueType	GetLinearGrowthSize () const
virtual void	SetGrowthStrategy (GrowthStrategyType _arg)
virtual GrowthStrategyType	GetGrowthStrategy () const
Public Member Functions inherited from itk::Object
unsigned long	AddObserver (const EventObject &event, Command *)
unsigned long	AddObserver (const EventObject &event, Command *) const
virtual void	DebugOff () const
virtual void	DebugOn () const
Command *	GetCommand (unsigned long tag)
bool	GetDebug () const
MetaDataDictionary &	GetMetaDataDictionary (void)
const MetaDataDictionary &	GetMetaDataDictionary (void) const
virtual ModifiedTimeType	GetMTime () const
virtual const TimeStamp &	GetTimeStamp () const
bool	HasObserver (const EventObject &event) const
void	InvokeEvent (const EventObject &)
void	InvokeEvent (const EventObject &) const
virtual void	Modified () const
virtual void	Register () const
void	RemoveAllObservers ()
void	RemoveObserver (unsigned long tag)
void	SetDebug (bool debugFlag) const
void	SetMetaDataDictionary (const MetaDataDictionary &rhs)
virtual void	SetReferenceCount (int)
virtual void	UnRegister () const
Public Member Functions inherited from itk::LightObject
virtual void	Delete ()
virtual int	GetReferenceCount () const
	itkCloneMacro (Self)
void	Print (std::ostream &os, Indent indent=0) const

Static Public Member Functions
static Pointer	New ()
Static Public Member Functions inherited from itk::Object
static bool	GetGlobalWarningDisplay ()
static void	GlobalWarningDisplayOff ()
static void	GlobalWarningDisplayOn ()
static Pointer	New ()
static void	SetGlobalWarningDisplay (bool flag)
Static Public Member Functions inherited from itk::LightObject
static void	BreakOnError ()
static Pointer	New ()

Protected Member Functions
SizeValueType	GetGrowthSize ()
	ObjectStore ()
virtual void	PrintSelf (std::ostream &os, Indent indent) const
	~ObjectStore ()
Protected Member Functions inherited from itk::Object
	Object ()
bool	PrintObservers (std::ostream &os, Indent indent) const
virtual void	SetTimeStamp (const TimeStamp &time)
virtual	~Object ()
Protected Member Functions inherited from itk::LightObject
virtual LightObject::Pointer	InternalClone () const
	LightObject ()
virtual void	PrintHeader (std::ostream &os, Indent indent) const
virtual void	PrintTrailer (std::ostream &os, Indent indent) const
virtual	~LightObject ()

Private Member Functions
	ObjectStore (const Self &)
void	operator= (const Self &)

Private Attributes
FreeListType	m_FreeList
GrowthStrategyType	m_GrowthStrategy
SizeValueType	m_LinearGrowthSize
SizeValueType	m_Size
std::vector< MemoryBlock >	m_Store

Additional Inherited Members
Protected Types inherited from itk::LightObject
typedef int	InternalReferenceCountType
Protected Attributes inherited from itk::LightObject
InternalReferenceCountType	m_ReferenceCount
SimpleFastMutexLock	m_ReferenceCountLock

Member Typedef Documentation

template<class TObjectType >

typedef SmartPointer< const Self > itk::ObjectStore< TObjectType >::ConstPointer

Definition at line 70 of file itkObjectStore.h.

template<class TObjectType >

typedef std::vector< ObjectType * > itk::ObjectStore< TObjectType >::FreeListType

Type of list for storing pointers to free memory.

Definition at line 82 of file itkObjectStore.h.

template<class TObjectType >

typedef TObjectType itk::ObjectStore< TObjectType >::ObjectType

Type of the objects in storage.

Definition at line 76 of file itkObjectStore.h.

template<class TObjectType >

typedef SmartPointer< Self > itk::ObjectStore< TObjectType >::Pointer

Definition at line 69 of file itkObjectStore.h.

template<class TObjectType >

typedef ObjectStore itk::ObjectStore< TObjectType >::Self

Standard typedefs.

Definition at line 67 of file itkObjectStore.h.

template<class TObjectType >

typedef Object itk::ObjectStore< TObjectType >::Superclass

Definition at line 68 of file itkObjectStore.h.

Member Enumeration Documentation

template<class TObjectType >

enum itk::ObjectStore::GrowthStrategyType

Type of memory allocation strategy

Enumerator:

LINEAR_GROWTH
EXPONENTIAL_GROWTH

Definition at line 85 of file itkObjectStore.h.

Constructor & Destructor Documentation

template<class TObjectType >

itk::ObjectStore< TObjectType >::ObjectStore ( )

protected

template<class TObjectType >

itk::ObjectStore< TObjectType >::~ObjectStore ( )

protected

template<class TObjectType >

itk::ObjectStore< TObjectType >::ObjectStore ( const Self &  )

private

Member Function Documentation

template<class TObjectType >

ObjectType* itk::ObjectStore< TObjectType >::Borrow

(

)

Borrow a pointer to an object from the memory store.

template<class TObjectType >

void itk::ObjectStore< TObjectType >::Clear

(

)

Frees all memory in the container

template<class TObjectType >

virtual::itk::LightObject::Pointer itk::ObjectStore< TObjectType >::CreateAnother ( void  ) const

virtual

Create an object from an instance, potentially deferring to a factory. This method allows you to create an instance of an object that is exactly the same type as the referring object. This is useful in cases where an object has been cast back to a base class.

Reimplemented from itk::Object.

template<class TObjectType >

SizeValueType itk::ObjectStore< TObjectType >::GetGrowthSize ( )

protected

Returns a new size to grow.

template<class TObjectType >

virtual GrowthStrategyType itk::ObjectStore< TObjectType >::GetGrowthStrategy ( ) const

virtual

Set/Get the growth strategy.

template<class TObjectType >

virtual SizeValueType itk::ObjectStore< TObjectType >::GetLinearGrowthSize ( ) const

virtual

Set/Get the linear growth size

template<class TObjectType >

virtual const char* itk::ObjectStore< TObjectType >::GetNameOfClass ( ) const

virtual

Run-time type information (and related methods).

Reimplemented from itk::Object.

template<class TObjectType >

virtual SizeValueType itk::ObjectStore< TObjectType >::GetSize ( ) const

virtual

Returns the size of the container. This is not the number of objects available, but the total number of objects allocated.

template<class TObjectType >

static Pointer itk::ObjectStore< TObjectType >::New ( )

static

Method for creation through the object factory.

template<class TObjectType >

void itk::ObjectStore< TObjectType >::operator= ( const Self &  )

private

template<class TObjectType >

virtual void itk::ObjectStore< TObjectType >::PrintSelf ( std::ostream &  os, Indent  indent  ) const

protectedvirtual

Methods invoked by Print() to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from itk::Object.

template<class TObjectType >

void itk::ObjectStore< TObjectType >::Reserve

(

SizeValueType

n

)

Ensures that there are at least n elements allocated in the storage container. Will not shrink the container, but may enlarge the container.

template<class TObjectType >

void itk::ObjectStore< TObjectType >::Return

(

ObjectType *

p

)

Return a pointer to the memory store for reuse. WARNING: The ObjectStore assumes a pointer is returned exactly once after each time it has been borrowed.

template<class TObjectType >

virtual void itk::ObjectStore< TObjectType >::SetGrowthStrategy ( GrowthStrategyType  _arg )

virtual

Set/Get the growth strategy.

template<class TObjectType >

void itk::ObjectStore< TObjectType >::SetGrowthStrategyToExponential ( )

inline

Set growth strategy to exponential

Definition at line 122 of file itkObjectStore.h.

template<class TObjectType >

void itk::ObjectStore< TObjectType >::SetGrowthStrategyToLinear ( )

inline

Set growth strategy to linear

Definition at line 126 of file itkObjectStore.h.

template<class TObjectType >

virtual void itk::ObjectStore< TObjectType >::SetLinearGrowthSize ( SizeValueType  _arg )

virtual

Set/Get the linear growth size

template<class TObjectType >

void itk::ObjectStore< TObjectType >::Squeeze

(

)

Attempts to free memory that is not in use and shrink the size of the container. Not guaranteed to do anything.

Member Data Documentation

template<class TObjectType >

FreeListType itk::ObjectStore< TObjectType >::m_FreeList

private

Pointers to objects available for borrowing.

Definition at line 162 of file itkObjectStore.h.

template<class TObjectType >

GrowthStrategyType itk::ObjectStore< TObjectType >::m_GrowthStrategy

private

Definition at line 156 of file itkObjectStore.h.

template<class TObjectType >

SizeValueType itk::ObjectStore< TObjectType >::m_LinearGrowthSize

private

Definition at line 159 of file itkObjectStore.h.

template<class TObjectType >

SizeValueType itk::ObjectStore< TObjectType >::m_Size

private

Definition at line 158 of file itkObjectStore.h.

template<class TObjectType >

std::vector< MemoryBlock > itk::ObjectStore< TObjectType >::m_Store

private

A list of MemoryBlocks that have been allocated.

Definition at line 165 of file itkObjectStore.h.

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

• itkObjectStore.h