Package org.geotools.data

Class DefaultFeatureResults

Object

DataFeatureCollection

DefaultFeatureResults

All Implemented Interfaces:

SimpleFeatureCollection, FeatureCollection<SimpleFeatureType,SimpleFeature>

public class DefaultFeatureResults
extends DataFeatureCollection

Generic "results" of a query, class.

Please optimize this class when use with your own content. For example a "ResultSet" make a great cache for a JDBCDataStore, a temporary copy of an original file may work for shapefile etc.

Author:

Jody Garnett, Refractions Research

Field Summary

Fields

Modifier and Type	Field	Description
protected SimpleFeatureSource	featureSource	Feature source used to aquire features, note we are only a "view" of this FeatureSource, its contents, transaction and events need to be forwarded through this collection api to simplier code such as renderers.
protected Query	query	Query used to define this subset of features from the feature source
protected MathTransform	transform

Fields inherited from class DataFeatureCollection

id, listeners, schema

Constructor Summary

Constructors

Constructor	Description
DefaultFeatureResults(SimpleFeatureSource source, Query query)	FeatureResults query against featureSource.

Method Summary

Modifier and Type	Method	Description
protected FeatureReader<SimpleFeatureType,SimpleFeature>	boundsReader()	Retrieve a FeatureReader for the geometry attributes only, designed for bounds computation
SimpleFeatureCollection	collection()
ReferencedEnvelope	getBounds()	Returns the bounding box of this FeatureResults
int	getCount()	Number of Features in this query.
SimpleFeatureType	getSchema()	FeatureSchema for provided query.
protected Transaction	getTransaction()	Returns transaction from SimpleFeatureSource (if it is a FeatureStore), or Transaction.AUTO_COMMIT if it is not.
FeatureReader<SimpleFeatureType,SimpleFeature>	reader()	Retrieve a FeatureReader for this Query

Methods inherited from class DataFeatureCollection

accepts, add, addAll, addAll, addListener, clear, close, close, closeIterator, contains, containsAll, features, fireChange, fireChange, fireChange, getID, isEmpty, iterator, openIterator, purge, remove, removeAll, removeListener, retainAll, size, sort, subCollection, toArray, toArray, writer

Methods inherited from class Object

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

Field Detail

query

protected Query query

Query used to define this subset of features from the feature source

featureSource

protected SimpleFeatureSource featureSource

Feature source used to aquire features, note we are only a "view" of this FeatureSource, its contents, transaction and events need to be forwarded through this collection api to simplier code such as renderers.

transform

protected MathTransform transform

Constructor Detail

DefaultFeatureResults

public DefaultFeatureResults(SimpleFeatureSource source,
                             Query query)
                      throws IOException

FeatureResults query against featureSource.

Please note that is object will not be valid after the transaction has closed.

Really? I think it would be, it would just reflect the same query against the SimpleFeatureSource using AUTO_COMMIT.

Throws:

IOException

Method Detail

getSchema

public SimpleFeatureType getSchema()

FeatureSchema for provided query.

If query.retrieveAllProperties() is true the FeatureSource getSchema() will be returned.

If query.getPropertyNames() is used to limit the result of the Query a sub type will be returned based on FeatureSource.getSchema().

Specified by:

getSchema in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Overrides:

getSchema in class DataFeatureCollection

Returns:

FeatureType describing the "common" schema to all child features of this collection

getTransaction

protected Transaction getTransaction()

Returns transaction from SimpleFeatureSource (if it is a FeatureStore), or Transaction.AUTO_COMMIT if it is not.

Returns:

Transacstion this FeatureResults opperates against

reader

public FeatureReader<SimpleFeatureType,SimpleFeature> reader()
                                                            throws IOException

Retrieve a FeatureReader for this Query

Overrides:

reader in class DataFeatureCollection

Returns:

FeatureReader for this Query

Throws:

IOException - If results could not be obtained

boundsReader

protected FeatureReader<SimpleFeatureType,SimpleFeature> boundsReader()
                                                                     throws IOException

Retrieve a FeatureReader for the geometry attributes only, designed for bounds computation

Throws:

IOException

getBounds

public ReferencedEnvelope getBounds()

Returns the bounding box of this FeatureResults

This implementation will generate the correct results from reader() if the provided SimpleFeatureSource does not provide an optimized result via FeatureSource.getBounds( Query ). If the feature has no geometry, then an empty envelope is returned.

Specified by:

getBounds in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Specified by:

getBounds in class DataFeatureCollection

Returns:

An Envelope containing the total bounds of this collection.

Throws:

DataSourceException - See IOException

See Also:

org.geotools.data.FeatureResults#getBounds()

getCount

public int getCount()
             throws IOException

Number of Features in this query.

This implementation will generate the correct results from reader() if the provided SimpleFeatureSource does not provide an optimized result via FeatureSource.getCount( Query ).

Specified by:

getCount in class DataFeatureCollection

Throws:

IOException - If feature could not be read

DataSourceException - See IOException

See Also:

org.geotools.data.FeatureResults#getCount()

collection

public SimpleFeatureCollection collection()
                                   throws IOException

Throws:

IOException