IlvDefaultObjectSDOTileLoader Class Reference

This class implements an IlvTileLoader to load tiles from Oracle 9i Spatial, using the SDO object model. More...

#include <ilviews/maps/format/oracle/objectmodel/8itileload.h>

Inheritance diagram for IlvDefaultObjectSDOTileLoader:

List of all members.

Public Member Functions
	IlvDefaultObjectSDOTileLoader (const IlvMapAdapter *mapAdapter, IldDbms *dbms, const char *tableName, const char *geometryColumnName, IlDouble tileWidth, IlDouble tileHeight, const char *xDimensionName=0, const char *yDimensionName=0, const char *keyColumnName=0, const IlvCoordinate *upperLeft=0, const IlvCoordinate *lowerRight=0)
	Initializes an instance of IlvDefaultObjectSDOTileLoader.
virtual IlvMapsError	dbmsRestored ()
	Called by the IlvSDOLayer read from an .ilv file, after the connection to an Oracle SDO database has been restored.
IlUInt	getColArraySize () const
	Returns the DbLink fetch array size parameter passed to the setRequestParameters method. The default value is 10.
virtual IlvObjectSDOFeatureIterator *	getFeatureIterator (IldRequest *request, const char *geometryColumnName, IlvObjectSDOKeyExtractor *keyExtractor, const char *xDimensionName, const char *yDimensionName, IlvMapsError &error)
	Returns the instance of IlvObjectSDOFeatureIterator that is used by the tile loader.
const char *	getLayerName ()
	Returns the name of the SDO layer of this tile loader.
virtual IldRequest *	getRequest (IlvTile *tile)
	Returns the IldRequest containing the SDO geometries that intersect the specified tile.
char **	getRequestParameters () const
	Returns the five parameters (a copy of each) of the internal request used for load-on-demand.
virtual IlvRect *	getSize ()
	Returns the bounding box of the data set managed by the tile loader.
IlUShort	getTileGroupingCount () const
	Returns the number of tiles to be loaded in one unique request.
virtual const IlvRect &	getTileOrigin () const
	Returns the origin tile used by the load-on demand mechanism.
IlBoolean	isClippingRequest () const
	Indicates whether the strict clipping policy is set or not.
virtual IlvMapsError	load (IlvTile *tile)
	Virtual method implemented in the subclasses.
void	setClippingRequest (IlBoolean set)
	Sets or unsets strict clipping policy.
virtual IlvMapsError	setRequestParameters (const char *selectClause="*", const char *fromClause=0, const char *whereClause=0, const char *spatialOperator="mdsys.sdo_filter", const char *spatialOperatorParams="querytype=window", IlUInt colArraySize=10)
	Sets some parameters in order to tune the request that is used by an IlvTile.
void	setTileGroupingCount (IlUShort nb)
	Sets the number of tiles to be loaded in one unique request.

---

Detailed Description

This class implements an IlvTileLoader to load tiles from Oracle 9i Spatial, using the SDO object model.

Library: ilvdbmaps

This tile loader is optimized for speed performance thanks to the tile grouping capacity that can be used through the IlvDefaultObjectSDOTileLoader::setTileGroupingCount method.

See also:

IlvObjectSDOLayer

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Constructor & Destructor Documentation

IlvDefaultObjectSDOTileLoader::IlvDefaultObjectSDOTileLoader	(	const IlvMapAdapter *	mapAdapter,
		IldDbms *	dbms,
		const char *	tableName,
		const char *	geometryColumnName,
		IlDouble	tileWidth,
		IlDouble	tileHeight,
		const char *	xDimensionName = 0,
		const char *	yDimensionName = 0,
		const char *	keyColumnName = 0,
		const IlvCoordinate *	upperLeft = 0,
		const IlvCoordinate *	lowerRight = 0
	)

Initializes an instance of IlvDefaultObjectSDOTileLoader.

Initializes an instance of IlvDefaultObjectSDOTileLoader to load data from the layer, specified by tableName, the name of the table containing the layer and geometryColumnName, the name of the column containing the geometry.

Parameters:

	mapAdapter	The map adapter used by the loader.
	dbms	The IldDbms connection to an Oracle database.
	tableName	The name of the layer table to be loaded.
	geometryColumnName	The name of the geometry column of the layer. This parameter is useful if the layer has more than one geometry column. If your layer has only one geometry column, just set this parameter to 0.
	tileWidth	The width of one Load On Demand tile. The width must be given in manager coordinate system (it will be adapted by the map adapter passed as argument).
	tileHeight	The height of one Load On Demand tile. The Height must be given in manager coordinate system (it will be adapted by the map adapter passed as argument).
	xDimensionName	The name of the X dimension. If set to 0, the index of the X dimension in the metadata table (in the SDO_DIM_ARRAY) will be considered as 0.
	yDimensionName	The name of the Y dimension. If set to 0, the index of the Y dimension in the metadata table (in the SDO_DIM_ARRAY) will be considered as 1.
	keyColumnName	The name of the column containing an ID considered as a Key for each geometry. If this parameter is set, then the key value extracted from the keyColumnName column is associated to the IlvMapFeature. The interest of this is that a map feature containing a geometry that belongs to multiple tiles will be loaded just once.
	upperLeft	The upper left corner of the layer extent (manager coordinate system). If set to 0, the corner is defaulted to the one available in the geometry metadata table.
	lowerRight	The lower right corner of the layer extent (manager coordinate system). If set to 0, the corner is defaulted to the one available in the geometry metadata table.

See also:

IlvObjectSDOKeyExtractor

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Member Function Documentation

virtual IlvMapsError IlvDefaultObjectSDOTileLoader::dbmsRestored

(

)

[virtual]

Called by the IlvSDOLayer read from an .ilv file, after the connection to an Oracle SDO database has been restored.

Returns:

An IlvMapsError code.

Reimplemented from IlvSDOTileLoader.

IlUInt IlvDefaultObjectSDOTileLoader::getColArraySize

(

)

const

Returns the DbLink fetch array size parameter passed to the setRequestParameters method. The default value is 10.

Returns:

The fetch array size value.

See also:

IlvDefaultObjectSDOTileLoader::setRequestParameters

virtual IlvObjectSDOFeatureIterator* IlvDefaultObjectSDOTileLoader::getFeatureIterator	(	IldRequest *	request,
		const char *	geometryColumnName,
		IlvObjectSDOKeyExtractor *	keyExtractor,
		const char *	xDimensionName,
		const char *	yDimensionName,
		IlvMapsError &	error
	)			[virtual]

Returns the instance of IlvObjectSDOFeatureIterator that is used by the tile loader.

You can override this method in order to use your own feature iterator.

Parameters:

	request	The IldRequest from which geometries are read.
	geometryName	The name of the column containing geometries.
	keyExtractor	The extractor that can extract featureIDs from the request rows.
	xDimensionName	The name of the X dimension.
	yDimensionName	The name of the Y dimension.
	error	The error that may have been produced by the method.

Returns:

The instance of IlvObjectSDOFeatureIterator used by the tile loader.

virtual IldRequest* IlvDefaultObjectSDOTileLoader::getRequest

(

IlvTile *

tile

)

[virtual]

Returns the IldRequest containing the SDO geometries that intersect the specified tile.

Returns 0 and must be implemented in the subclass.

See also:

IlvSDOTileLoader::load

Parameters:

tile

The tile to be filled with the SDO geometries.

Reimplemented from IlvSDOTileLoader.

char** IlvDefaultObjectSDOTileLoader::getRequestParameters

(

)

const

Returns the five parameters (a copy of each) of the internal request used for load-on-demand.

It returns them in the same order that the one used in the setRequestParameters method. The returned strings are allocated with the new [] operator and should then be deallocated thanks to the delete [] operator.

Returns:

The parameters of the internal request used for load-on-demand.

See also:

IlvDefaultObjectSDOTileLoader::setRequestParameters

virtual IlvRect* IlvDefaultObjectSDOTileLoader::getSize

(

)

[virtual]

Returns the bounding box of the data set managed by the tile loader.

If the bounding box cannot be computed, this method can return 0. The IlvSDOLayer using this object will have an undefined size.

Returns:

0

Reimplemented from IlvSDOTileLoader.

IlUShort IlvDefaultObjectSDOTileLoader::getTileGroupingCount

(

)

const

Returns the number of tiles to be loaded in one unique request.

See also:

IlvDefaultObjectSDOTileLoader::setTileGroupingCount

IlBoolean IlvDefaultObjectSDOTileLoader::isClippingRequest

(

)

const

Indicates whether the strict clipping policy is set or not.

Returns whether the tile loader will perform a strict clipping. When the strict clipping mode is set, the loaded geometries are clipped so that they intersect the bounding box of the IlvTile that has loaded them.

The default behavior of this tile loader is to not perform this strict clipping.

Returns:

IlTrue if this tile loader clips strictly the geometries.

See also:

setClippingRequest

virtual IlvMapsError IlvDefaultObjectSDOTileLoader::load

(

IlvTile *

tile

)

[virtual]

Virtual method implemented in the subclasses.

Returns:

IlvMaps::NoError().

Reimplemented from IlvSDOTileLoader.

void IlvDefaultObjectSDOTileLoader::setClippingRequest

(

IlBoolean

set

)

Sets or unsets strict clipping policy.

Sets whether this tile loader performs a strict clipping. When the strict clipping mode is set, the loaded geometries are clipped so that they intersect the bounding box of the IlvTile that has loaded them.

The default behavior of this tile loader is to not perform this strict clipping.

Parameters:

set

If IlTrue, the strict clipping mode is set.

See also:

isClippingRequest

virtual IlvMapsError IlvDefaultObjectSDOTileLoader::setRequestParameters	(	const char *	selectClause = "*",
		const char *	fromClause = 0,
		const char *	whereClause = 0,
		const char *	spatialOperator = "mdsys.sdo_filter",
		const char *	spatialOperatorParams = "querytype=window",
		IlUInt	colArraySize = 10
	)			[virtual]

Sets some parameters in order to tune the request that is used by an IlvTile.

The used request is of type: "select selectClause from fromClause where whereClause and mdsys.spatialOperator (layerName.geometryColumnName, ... ), 'spatialOperatorParams') = 'TRUE'"
For instance, calling the method with the following arguments will lead to a load-on-demand only on geometries, the attributes being ignored (it supposes that the geometry column name is "GEOMETRY"): setRequestParameters("GEOMETRY");
If you do not want to use an argument of the function, pass it as 0.

Parameters:

	selectClause	The select clause of the request. The default value is "*".
	fromClause	The from clause of the request. The default value is the name of the SDO layer.
	whereClause	The where clause of the request.
	spatialOperator	The spatial operator used in the request. The default value is "mdsys.sdo_filter". For more information about spatial operators, please refer to the User's Manual.
	spatialOperatorParams	The parameters of the spatial operator. The default value is "querytype=window".
	colArraySize	The DbLink fetch array mode is activated. If you pass 0, the parameter is ignored. The value recommended by Oracle is 10. See IldRequest::setColArraySize.

void IlvDefaultObjectSDOTileLoader::setTileGroupingCount

(

IlUShort

nb

)

Sets the number of tiles to be loaded in one unique request.

This is particularly useful for the load on demand where you can group a given number of tiles to be loaded together (when for instance the zoom factor is important so that you are visualizing a certain number of tiles at the same time).