itk::ObjectStore< TObjectType > Class Template Reference

#include <itkObjectStore.h>

Inheritance diagram for itk::ObjectStore< TObjectType >:

Collaboration diagram for itk::ObjectStore< TObjectType >:

List of all members.

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 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	Squeeze ()
virtual void	SetLinearGrowthSize (SizeValueType _arg)
virtual SizeValueType	GetLinearGrowthSize () const
virtual void	SetGrowthStrategy (GrowthStrategyType _arg)
virtual GrowthStrategyType	GetGrowthStrategy () const
Static Public Member Functions
static Pointer	New ()
Protected Member Functions
SizeValueType	GetGrowthSize ()
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
void	SetGrowthStrategyToLinear ()
	ObjectStore ()
	~ObjectStore ()
virtual void	PrintSelf (std::ostream &os, Indent indent) const

---

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.

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Member Typedef Documentation

template<class TObjectType >

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

Reimplemented from itk::Object.

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

Reimplemented from itk::Object.

Definition at line 69 of file itkObjectStore.h.

template<class TObjectType >

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

Standard typedefs.

Reimplemented from itk::Object.

Definition at line 67 of file itkObjectStore.h.

template<class TObjectType >

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

Reimplemented from itk::Object.

Definition at line 68 of file itkObjectStore.h.

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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]

Set growth strategy to linear

template<class TObjectType >

itk::ObjectStore< TObjectType >::~ObjectStore

(

)

[protected]

Set growth strategy to linear

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.

Reimplemented from itk::Object.

template<class TObjectType >

void itk::ObjectStore< TObjectType >::operator=

(

const Self &

)

[private]

Mutex lock to protect modification to the reference count

Reimplemented from itk::Object.

template<class TObjectType >

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

Set growth strategy to linear

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.

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Member Data Documentation

template<class TObjectType >

FreeListType itk::ObjectStore< TObjectType >::m_FreeList [private]

Pointers to objects available for borrowing.

Definition at line 161 of file itkObjectStore.h.

template<class TObjectType >

GrowthStrategyType itk::ObjectStore< TObjectType >::m_GrowthStrategy [private]

Definition at line 155 of file itkObjectStore.h.

template<class TObjectType >

SizeValueType itk::ObjectStore< TObjectType >::m_LinearGrowthSize [private]

Definition at line 158 of file itkObjectStore.h.

template<class TObjectType >

SizeValueType itk::ObjectStore< TObjectType >::m_Size [private]

Definition at line 157 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 164 of file itkObjectStore.h.

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

• itkObjectStore.h