BFeaturesOnDisk Class Reference

#include <BFeaturesOnDisk.h>

Inheritance diagram for BFeaturesOnDisk:

[legend]

List of all members.

---

Detailed Description

A collection of BFeature objects that exists on a disk.

Public Member Functions
virtual void	Add (const BFeatureCollection &features)
	Appends the BFeature objects in the specified collection to this collection.
virtual void	Add (const BFeaturePtr &feature)
	Adds a BFeature to this collection.
virtual void	Add (const BFeature &feature)
	Copies the specified BFeature and adds it to this collection.
	BFeaturesOnDisk (const BFeaturesOnDisk &feats)
	Copy constructor.
	BFeaturesOnDisk (const BString &cacheName, Int32 pageSize)
	Constructor.
	BFeaturesOnDisk ()
	Default constructor.
virtual void	Clear (void)
	Removes all BFeature objects from this collection.
virtual const BFeaturePtr	GetAt (size_t index, bool inclCachedAttrs=true) const
	Gets the BFeature at the specified index in this collection.
virtual BFeaturePtr	GetAt (size_t index, bool inclCachedAttrs=true)
	Gets the BFeature at the specified index in this collection.
virtual size_t	GetCount (void) const
	Gets the number of BFeature objects in this collection.
virtual void	Release (size_t index)
	Releases the memory associated with a BFeature.
virtual void	Remove (size_t index)
	Removes a BFeature from this collection.
virtual void	Reserve (size_t size)
	Reserves space for the requested number of elements in this collection.
virtual void	Transform (const BTransform &cst)
	Transforms the geometry of each BFeature in this collection to a different coordinate system.
virtual void	TransformReverse (const BTransform &cst)
	Transforms the geometry of each BFeature in this collection to a different coordinate system using the "reverse" of the BTransform.
virtual	~BFeaturesOnDisk ()
	Destructor.
Protected Member Functions
BRect	ComputeMBR (void) const
	Computes the minimum bounding rectangle for the BFeature objects in this collection.
BFeaturePtr	ReadFeatureFromCache (Int32 id, bool inclAttrs) const
	Reads a BFeature from the BDiskCache.
void	RemoveFeatureFromCache (Int32 id)
	Removes a BFeature from the BDiskCache.
void	ReplaceFeatureInCache (Int32 id, BFeature &feature)
	Replace a BFeature in the BDiskCache.
Int32	WriteFeatureToCache (const BFeature &feature)
	Writes a BFeature to the BDiskCache.
Protected Attributes
BString	m_cacheName
	The base file name for the cache.
Int32Vector	m_featureIDs
	The feature ID index.
Int32	m_pageSize
	The page size for the cache.
BDiskCachePtr	m_pCache
	The BDiskCache that holds the data for this collection.

---

Constructor & Destructor Documentation

BFeaturesOnDisk

(

)

Default constructor.

This constructor will create an empty collection.

BFeaturesOnDisk	(	const BString &	cacheName,
		Int32	pageSize
	)

Constructor.

This constructor will create an empty collection that uses the specified cache.

Parameters:

	cacheName	The base file name to be used for the cache. If an empty string is specified, a temporary file name will be generated.
	pageSize	The page size to be used in the cache.

BFeaturesOnDisk

(

const BFeaturesOnDisk &

feats

)

Copy constructor.

Parameters:

feats

The BFeaturesOnDisk object to copy.

virtual ~BFeaturesOnDisk

(

)

[inline, virtual]

Destructor.

---

Member Function Documentation

virtual void Add

(

const BFeatureCollection &

features

)

[virtual]

Appends the BFeature objects in the specified collection to this collection.

Parameters:

features

The collection of BFeature objects to be added.

Exceptions:

BUnknownGeometryException

This exception will be thrown if the geometry associated with the specified feature is not of the correct class.

Implements BFeatureCollection.

virtual void Add

(

const BFeaturePtr &

feature

)

[virtual]

Adds a BFeature to this collection.

Parameters:

feature

Pointer to the feature to be added.

Exceptions:

BUnknownGeometryException

This exception will be thrown if the geometry associated with the specified feature is not of the correct class.

Implements BFeatureCollection.

virtual void Add

(

const BFeature &

feature

)

[virtual]

Copies the specified BFeature and adds it to this collection.

Parameters:

feature

The BFeature to be copied and added to this collection.

Exceptions:

BUnknownGeometryException

This exception will be thrown if the geometry associated with the specified feature is not of the correct class.

Implements BFeatureCollection.

virtual void Clear

(

void

)

[virtual]

Removes all BFeature objects from this collection.

Derived classes should call Clear method in the base class implementation.

Reimplemented from BFeatureCollection.

BRect ComputeMBR

(

void

)

const [protected, virtual]

Computes the minimum bounding rectangle for the BFeature objects in this collection.

Returns:

The minimum bounding rectangle.

Implements BFeatureCollection.

virtual const BFeaturePtr GetAt	(	size_t	index,
		bool	inclCachedAttrs = true
	)			const [virtual]

Gets the BFeature at the specified index in this collection.

Parameters:

	index	The zero-based index of the desired BFeature.
	inclCachedAttrs	Indicates whether the returned feature will contain attributes. This applies only when the features are stored in a disk cache, and can be used to improve performance in applications where attributes are not needed. If the features are stored in memory, this has no effect.

Returns:

The BFeature at the specified index.

Exceptions:

BIndexOutOfBoundsException

This exception will be thrown if the specified index does not correspond to a BFeature in this collection.

Implements BFeatureCollection.

virtual BFeaturePtr GetAt	(	size_t	index,
		bool	inclCachedAttrs = true
	)			[virtual]

Gets the BFeature at the specified index in this collection.

Parameters:

	index	The zero-based index of the desired BFeature.
	inclCachedAttrs	Indicates whether the returned feature will contain attributes. This applies only when the features are stored in a disk cache, and can be used to improve performance in applications where attributes are not needed. If the features are stored in memory, this has no effect.

Returns:

The BFeature at the specified index.

Exceptions:

BIndexOutOfBoundsException

This exception will be thrown if the specified index does not correspond to a BFeature in this collection.

Implements BFeatureCollection.

virtual size_t GetCount

(

void

)

const [inline, virtual]

Gets the number of BFeature objects in this collection.

Returns:

The number of BFeature objects in this collection.

Implements BFeatureCollection.

BFeaturePtr ReadFeatureFromCache	(	Int32	id,
		bool	inclAttrs
	)			const [protected]

Reads a BFeature from the BDiskCache.

Parameters:

	id	The ID for the BFeature to read from the BDiskCache.
	inclAttrs	Indicates whether or not to include the attributes when reading a feature from the cache.

Returns:

The BFeature object.

virtual void Release

(

size_t

index

)

[inline, virtual]

Releases the memory associated with a BFeature.

This method has no effect on features stored in the disk cache.

Parameters:

index

The zero-based index of the BFeature to be released.

Implements BFeatureCollection.

virtual void Remove

(

size_t

index

)

[virtual]

Removes a BFeature from this collection.

Parameters:

index

The zero-based index of the BFeature to be removed.

Exceptions:

BIndexOutOfBoundsException

This exception will be thrown if the specified index does not correspond to a BFeature in this collection.

Implements BFeatureCollection.

void RemoveFeatureFromCache

(

Int32

id

)

[protected]

Removes a BFeature from the BDiskCache.

Parameters:

id

The ID of the BFeature to be removed.

void ReplaceFeatureInCache	(	Int32	id,
		BFeature &	feature
	)			[protected]

Replace a BFeature in the BDiskCache.

Parameters:

	id	The id of the BFeature to be replaced.
	feature	The BFeature object that will be written to the BDiskCache.

virtual void Reserve

(

size_t

size

)

[inline, virtual]

Reserves space for the requested number of elements in this collection.

Parameters:

size

The number of elements for which space shall be reserved.

Implements BFeatureCollection.

virtual void Transform

(

const BTransform &

cst

)

[virtual]

Transforms the geometry of each BFeature in this collection to a different coordinate system.

Parameters:

cst

The BTransform that defines the transformation.

Implements BFeatureCollection.

virtual void TransformReverse

(

const BTransform &

cst

)

[virtual]

Transforms the geometry of each BFeature in this collection to a different coordinate system using the "reverse" of the BTransform.

Parameters:

cst

The BTransform that defines the transformation.

Implements BFeatureCollection.

Int32 WriteFeatureToCache

(

const BFeature &

feature

)

[protected]

Writes a BFeature to the BDiskCache.

Parameters:

feature

The BFeature to be written to the BDiskCache.

Returns:

The BFeature's cache ID, which will be used to read the BFeature out of the BDiskCache.

---

Member Data Documentation

BString m_cacheName [protected]

The base file name for the cache.

Int32Vector m_featureIDs [protected]

The feature ID index.

Int32 m_pageSize [protected]

The page size for the cache.

BDiskCachePtr m_pCache [protected]

The BDiskCache that holds the data for this collection.

---

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

• BFeaturesOnDisk.h

---

GeoTranslate 5.0 From Blue Marble Geographics