org.geotools.data
Class AbstractFeatureSource

java.lang.Object
  org.geotools.data.AbstractFeatureSource

All Implemented Interfaces:

FeatureSource

Direct Known Subclasses:

AbstractFeatureStore, WFSFeatureSource

public abstract class AbstractFeatureSource

extends java.lang.Object

implements FeatureSource

This is a starting point for providing your own FeatureSource implementation.

Subclasses must implement:

• getDataStore()
• getSchema()
• addFeatureListener()
• removeFeatureListener()

You may find a FeatureSource implementations that is more specific to your needs - such as JDBCFeatureSource.

For an example of this class customized for use please see MemoryDataStore.

Author:

Jody Garnett, Refractions Research Inc

Constructor Summary

AbstractFeatureSource()

Method Summary

com.vividsolutions.jts.geom.Envelope	getBounds() Retrieve Bounds of all Features.
com.vividsolutions.jts.geom.Envelope	getBounds(Query query) Retrieve Bounds of Query results.
int	getCount(Query query) Retrieve total number of Query results.
FeatureCollection	getFeatures() Retrieve all Features.
FeatureCollection	getFeatures(Filter filter) Retrieve all Feature matching the Filter.
FeatureCollection	getFeatures(Query query) Provides an interface to for the Resutls of a Query.
Transaction	getTransaction() Retrieve the Transaction this FeatureSource is opperating against.
protected Query	namedQuery(Query query) Ensure query modified with typeName.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.geotools.data.FeatureSource

addFeatureListener, getDataStore, getSchema, removeFeatureListener

Constructor Detail

AbstractFeatureSource

public AbstractFeatureSource()

Method Detail

getTransaction

public Transaction getTransaction()

Retrieve the Transaction this FeatureSource is opperating against.

For a plain FeatureSource that cannot modify this will always be Transaction.AUTO_COMMIT.

Returns:

Transacstion FeatureSource is opperating against

getFeatures

public FeatureCollection getFeatures(Query query)

Provides an interface to for the Resutls of a Query.

Various queries can be made against the results, the most basic being to retrieve Features.

Specified by:

getFeatures in interface FeatureSource

Parameters:

query -

Returns:

See Also:

FeatureSource.getFeatures(org.geotools.data.Query)

getFeatures

public FeatureCollection getFeatures(Filter filter)
                              throws java.io.IOException

Retrieve all Feature matching the Filter.

Specified by:

getFeatures in interface FeatureSource

Parameters:

filter - Indicates features to retrieve

Returns:

FeatureResults indicating features matching filter

Throws:

java.io.IOException - If results could not be obtained

getFeatures

public FeatureCollection getFeatures()
                              throws java.io.IOException

Retrieve all Features.

Specified by:

getFeatures in interface FeatureSource

Returns:

FeatureResults of all Features in FeatureSource

Throws:

java.io.IOException - If features could not be obtained

getBounds

public com.vividsolutions.jts.geom.Envelope getBounds()
                                               throws java.io.IOException

Retrieve Bounds of all Features.

Currently returns null, consider getFeatures().getBounds() instead.

Subclasses may override this method to perform the appropriate optimization for this result.

Specified by:

getBounds in interface FeatureSource

Returns:

null representing the lack of an optimization

Throws:

java.io.IOException - DOCUMENT ME!

getBounds

public com.vividsolutions.jts.geom.Envelope getBounds(Query query)
                                               throws java.io.IOException

Retrieve Bounds of Query results.

Currently returns null, consider getFeatures( query ).getBounds() instead.

Subclasses may override this method to perform the appropriate optimization for this result.

Specified by:

getBounds in interface FeatureSource

Parameters:

query - Query we are requesting the bounds of

Returns:

null representing the lack of an optimization

Throws:

java.io.IOException - DOCUMENT ME!

namedQuery

protected Query namedQuery(Query query)

Ensure query modified with typeName.

This method will make copy of the provided query, using DefaultQuery, if query.getTypeName is not equal to getSchema().getTypeName().

Parameters:

query - Origional query

Returns:

Query with getTypeName() equal to getSchema().getTypeName()

getCount

public int getCount(Query query)
             throws java.io.IOException

Retrieve total number of Query results.

Currently returns -1, consider getFeatures( query ).getCount() instead.

Subclasses may override this method to perform the appropriate optimization for this result.

Specified by:

getCount in interface FeatureSource

Parameters:

query - Query we are requesting the count of

Returns:

-1 representing the lack of an optimization

Throws:

java.io.IOException - if there are errors getting the count