ilog.views.maps.format.oracle
Class IlvSDOTileLoader

java.lang.Object
  ilog.views.maps.format.oracle.IlvSDOTileLoader

All Implemented Interfaces:

IlvPersistentObject, IlvTileLoader

Direct Known Subclasses:

IlvDefaultObjectSDOTileLoader, IlvDefaultSDOTileLoader

public abstract class IlvSDOTileLoader
extends Object
implements IlvTileLoader

The base class to implement tile loaders for Oracle SDO.

See Also:

IlvSDOLayer

Constructor Summary

protected	IlvSDOTileLoader(IlvInputStream stream) Reads the tile loader from an IlvInputStream
protected	IlvSDOTileLoader(IlvSDOConnection connection) Initializes an instance of IlvSDOTileLoader

Method Summary

void	connectionRestored() This method is called by the IlvSDOLayer when it is read from an .ivl file, after the connection to an SDO database has been restored.
protected ResultSet	executeQuery(String query) Executes the specified query and prints a trace if the SQL traces are enabled.
IlvSDOConnection	getConnection() Returns the connection to the Oracle database.
abstract ResultSet	getResultSet(IlvTile tile) Returns the ResultSet containing the SDO geometries that intersect the specified tile.
abstract IlvRect	getSize() Returns the bounding box of the data set managed by the tile loader.
abstract IlvRect	getTileOrigin() Returns the coordinates of the origin tile used by the load-on demand mechanism.
boolean	isPersistent() Returns true.
void	load(IlvTile tile) Loads a tile from the Oracle database and adds the graphic objects to the layer of the tile.
void	release(IlvTile tile) Releases the content of a tile when required by the cache of the layer.
void	write(IlvOutputStream stream) Writes the tile loader to a JViews file.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

IlvSDOTileLoader

protected IlvSDOTileLoader(IlvSDOConnection connection)

Initializes an instance of IlvSDOTileLoader

Parameters:

connection - The connection to an Oracle database

IlvSDOTileLoader

protected IlvSDOTileLoader(IlvInputStream stream)
                    throws IlvReadFileException

Reads the tile loader from an IlvInputStream

Parameters:

stream - the input stream

Throws:

IlvReadFileException - if an error occurs while reading.

Method Detail

getTileOrigin

public abstract IlvRect getTileOrigin()
                               throws SQLException

Returns the coordinates of the origin tile used by the load-on demand mechanism.

Throws:

SQLException

getResultSet

public abstract ResultSet getResultSet(IlvTile tile)
                                throws SQLException

Returns the ResultSet containing the SDO geometries that intersect the specified tile. This method is called by load(IlvTile tile) when a tile needs to be loaded.

Parameters:

tile - The tile to be filled with the SDO geometries

Throws:

SQLException

See Also:

load(ilog.views.tiling.IlvTile)

getSize

public abstract IlvRect getSize()
                         throws SQLException

Returns the bounding box of the data set managed by the tile loader. If the bounding box cannot be computed, this method can return a null value. The IlvSDOLayer using this object will have an undefined size.

Throws:

SQLException

See Also:

IlvTiledLayer.getSize()

connectionRestored

public void connectionRestored()
                        throws SQLException

This method is called by the IlvSDOLayer when it is read from an .ivl file, after the connection to an SDO database has been restored.

Throws:

SQLException

load

public void load(IlvTile tile)
          throws Exception

Loads a tile from the Oracle database and adds the graphic objects to the layer of the tile. This method calls getResultSet to get the SDO geometries, transforms them into graphic objects using the renderer of the layer, and then adds the objects to the layer.

Specified by:

load in interface IlvTileLoader

Parameters:

tile - The tile to load

Throws:

Exception - if an error occurs while loading the tile.

See Also:

getResultSet(ilog.views.tiling.IlvTile)

release

public void release(IlvTile tile)

Releases the content of a tile when required by the cache of the layer.

Specified by:

release in interface IlvTileLoader

Parameters:

tile - The tile to release.

executeQuery

protected ResultSet executeQuery(String query)
                          throws SQLException

Executes the specified query and prints a trace if the SQL traces are enabled.

Parameters:

query - The SQL query

Throws:

SQLException - if an SQL error occurs.

See Also:

IlvSDOUtil.EnableSQLTraces(boolean)

getConnection

public IlvSDOConnection getConnection()

Returns the connection to the Oracle database.

write

public void write(IlvOutputStream stream)
           throws IOException

Writes the tile loader to a JViews file.

Specified by:

write in interface IlvPersistentObject

Specified by:

write in interface IlvTileLoader

Parameters:

stream - The output stream

Throws:

IOException - if a write exception occurs.

isPersistent

public boolean isPersistent()

Returns true.

Specified by:

isPersistent in interface IlvTileLoader