org.geotools.data
Class AbstractFeatureSource

Object
  AbstractFeatureSource

All Implemented Interfaces:

FeatureSource<SimpleFeatureType,SimpleFeature>, SimpleFeatureSource

Direct Known Subclasses:

AbstractFeatureStore, PropertyFeatureSource, WFSFeatureSource

public abstract class AbstractFeatureSource
extends Object
implements SimpleFeatureSource

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

Subclasses must implement:

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

You may find a SimpleFeatureSource 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

Field Summary

protected Set	hints
protected QueryCapabilities	queryCapabilities

Constructor Summary

AbstractFeatureSource()

AbstractFeatureSource(Set hints)
This constructors allows to set the supported hints

Method Summary

ReferencedEnvelope	getBounds() Retrieve Bounds of all Features.
ReferencedEnvelope	getBounds(Query query) Retrieve Bounds of Query results.
int	getCount(Query query) Retrieve total number of Query results.
abstract DataStore	getDataStore() Overrides to explicitly type narrow the return type to DataStore
SimpleFeatureCollection	getFeatures() Retrieve all Features.
SimpleFeatureCollection	getFeatures(Filter filter) Retrieve all Feature matching the Filter.
SimpleFeatureCollection	getFeatures(Query query) Provides an interface to for the Results of a Query.
ResourceInfo	getInfo() Returns information describing this FeatureSource which may include title, description and spatial parameters.
Name	getName() Returns the same name than the feature type (ie, getSchema().getName() to honor the simple feature land common practice of calling the same both the Features produces and their types
QueryCapabilities	getQueryCapabilities() Enquire what what query capabilities this FeatureSource natively supports.
Set	getSupportedHints() By default, no Hints are supported
Transaction	getTransaction() Retrieve the Transaction this SimpleFeatureSource is operating against.
protected Query	namedQuery(Query query) Ensure query modified with typeName.

Methods inherited from class Object

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

Methods inherited from interface FeatureSource

addFeatureListener, getSchema, removeFeatureListener

Field Detail

hints

protected Set hints

queryCapabilities

protected QueryCapabilities queryCapabilities

Constructor Detail

AbstractFeatureSource

public AbstractFeatureSource()

AbstractFeatureSource

public AbstractFeatureSource(Set hints)

This constructors allows to set the supported hints

Parameters:

hints -

Method Detail

getDataStore

public abstract DataStore getDataStore()

Overrides to explicitly type narrow the return type to DataStore

Specified by:

getDataStore in interface FeatureSource<SimpleFeatureType,SimpleFeature>

Returns:

the data source providing this FeatureSource

getName

public Name getName()

Returns the same name than the feature type (ie, getSchema().getName() to honor the simple feature land common practice of calling the same both the Features produces and their types

Specified by:

getName in interface FeatureSource<SimpleFeatureType,SimpleFeature>

Returns:

the name of the features accessible through this FeatureSource

Since:

2.5

See Also:

FeatureSource.getName()

getInfo

public ResourceInfo getInfo()

Description copied from interface: FeatureSource

Returns information describing this FeatureSource which may include title, description and spatial parameters. Note that in the returned ResourceInfo object, the distinction between feature name and schema (feature type) name applies as discussed for FeatureSource.getName().

Specified by:

getInfo in interface FeatureSource<SimpleFeatureType,SimpleFeature>

getQueryCapabilities

public QueryCapabilities getQueryCapabilities()

Description copied from interface: FeatureSource

Enquire what what query capabilities this FeatureSource natively supports. For example, whether queries can return sorted results.

Specified by:

getQueryCapabilities in interface FeatureSource<SimpleFeatureType,SimpleFeature>

Returns:

the native query capabilities of this FeatureSource

getTransaction

public Transaction getTransaction()

Retrieve the Transaction this SimpleFeatureSource is operating against.

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

Returns:

Transacstion SimpleFeatureSource is operating against

getFeatures

public SimpleFeatureCollection getFeatures(Query query)
                                    throws IOException

Provides an interface to for the Results of a Query.

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

Specified by:

getFeatures in interface FeatureSource<SimpleFeatureType,SimpleFeature>

Specified by:

getFeatures in interface SimpleFeatureSource

Parameters:

query -

Returns:

features retrieved by the Query

Throws:

IOException - if the underlying data source cannot be accessed.

See Also:

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

getFeatures

public SimpleFeatureCollection getFeatures(Filter filter)
                                    throws IOException

Retrieve all Feature matching the Filter.

Specified by:

getFeatures in interface FeatureSource<SimpleFeatureType,SimpleFeature>

Specified by:

getFeatures in interface SimpleFeatureSource

Parameters:

filter - Indicates features to retrieve

Returns:

FeatureResults indicating features matching filter

Throws:

IOException - If results could not be obtained

See Also:

Filter

getFeatures

public SimpleFeatureCollection getFeatures()
                                    throws IOException

Retrieve all Features.

Specified by:

getFeatures in interface FeatureSource<SimpleFeatureType,SimpleFeature>

Specified by:

getFeatures in interface SimpleFeatureSource

Returns:

FeatureResults of all Features in FeatureSource

Throws:

IOException - If features could not be obtained

getBounds

public ReferencedEnvelope getBounds()
                             throws 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<SimpleFeatureType,SimpleFeature>

Returns:

null representing the lack of an optimization

Throws:

IOException - DOCUMENT ME!

getBounds

public ReferencedEnvelope getBounds(Query query)
                             throws 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<SimpleFeatureType,SimpleFeature>

Parameters:

query - Query we are requesting the bounds of

Returns:

null representing the lack of an optimization

Throws:

IOException

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 - Original query

Returns:

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

getCount

public int getCount(Query query)
             throws 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<SimpleFeatureType,SimpleFeature>

Parameters:

query - Query we are requesting the count of

Returns:

-1 representing the lack of an optimization

Throws:

IOException - if there are errors getting the count

getSupportedHints

public Set getSupportedHints()

By default, no Hints are supported

Specified by:

getSupportedHints in interface FeatureSource<SimpleFeatureType,SimpleFeature>

Returns:

a set of RenderingHints#Key objects; may be empty but never null

See Also:

Hints.FEATURE_DETACHED, Hints.JTS_GEOMETRY_FACTORY, Hints.JTS_COORDINATE_SEQUENCE_FACTORY, Hints.JTS_PRECISION_MODEL, Hints.JTS_SRID, Hints.GEOMETRY_DISTANCE, Hints.FEATURE_2D