org.geotools.data
Class DefaultFeatureResults

java.lang.Object
  org.geotools.data.store.DataFeatureCollection
      org.geotools.data.DefaultFeatureResults

All Implemented Interfaces:

java.util.Collection, Feature, FeatureCollection, FeatureResults, ResourceCollection

Direct Known Subclasses:

JDBCFeatureCollection, WFSFeatureSource.WFSFeatureResults

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

Nested Class Summary

Nested classes inherited from class org.geotools.feature.Feature

Feature.NULL

Field Summary

protected FeatureSource	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

Constructor Summary

DefaultFeatureResults(FeatureSource source, Query query)
FeatureResults query against featureSource.

Method Summary

FeatureCollection	collection() Convert this set of results to a FeatureCollection.
com.vividsolutions.jts.geom.Envelope	getBounds() Returns the bounding box of this FeatureResults This implementation will generate the correct results from reader() if the provided FeatureSource does not provide an optimized result via FeatureSource.getBounds( Query ).
int	getCount() Number of Features in this query.
FeatureType	getSchema() FeatureSchema for provided query.
protected Transaction	getTransaction() Returns transaction from featureSource (if it is a FeatureStore), or Transaction.AUTO_COMMIT if it is not.
FeatureReader	reader() Retrieve a FeatureReader for this Query

Methods inherited from class org.geotools.data.store.DataFeatureCollection

accepts, add, addAll, addListener, clear, close, close, closeIterator, contains, containsAll, features, fireChange, fireChange, fireChange, getAttribute, getAttribute, getAttributes, getDefaultGeometry, getFeatureType, getID, getNumberOfAttributes, getParent, isEmpty, iterator, openIteartor, purge, remove, removeAll, removeListener, retainAll, setAttribute, setAttribute, setDefaultGeometry, setParent, size, sort, sort, subCollection, toArray, toArray, writer

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Collection

equals, hashCode

Field Detail

query

protected Query query

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

featureSource

protected FeatureSource 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.

Constructor Detail

DefaultFeatureResults

public DefaultFeatureResults(FeatureSource source,
                             Query query)

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 featuresource using AUTO_COMMIT.

Parameters:

source -

query -

Method Detail

getSchema

public FeatureType 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

Specified by:

getSchema in class DataFeatureCollection

Returns:

DOCUMENT ME!

Throws:

java.io.IOException - DOCUMENT ME!

DataSourceException - DOCUMENT ME!

getTransaction

protected Transaction getTransaction()

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

Returns:

Transacstion this FeatureResults opperates against

reader

public FeatureReader reader()
                     throws java.io.IOException

Retrieve a FeatureReader for this Query

Specified by:

reader in interface FeatureResults

Specified by:

reader in class DataFeatureCollection

Returns:

FeatureReader for this Query

Throws:

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

getBounds

public com.vividsolutions.jts.geom.Envelope getBounds()

Returns the bounding box of this FeatureResults

This implementation will generate the correct results from reader() if the provided FeatureSource 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 FeatureResults

Specified by:

getBounds in class DataFeatureCollection

Returns:

Throws:

DataSourceException - See IOException

See Also:

FeatureResults.getBounds()

getCount

public int getCount()
             throws java.io.IOException

Number of Features in this query.

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

Specified by:

getCount in interface FeatureResults

Specified by:

getCount in class DataFeatureCollection

Returns:

Throws:

java.io.IOException - If feature could not be read

DataSourceException - See IOException

See Also:

FeatureResults.getCount()

collection

public FeatureCollection collection()
                             throws java.io.IOException

Description copied from interface: FeatureResults

Convert this set of results to a FeatureCollection.

This method is logically the same as:

 public FeatureCollection collection() throws IOException {
     FeatureCollection collection = FeatureCollections.newCollection()
     for (FeatureReader r = reader(); r.hasNext();) {
         collection.add( r.next() );
     }
     return collection;  
 }
 

Specified by:

collection in interface FeatureResults

Specified by:

collection in class DataFeatureCollection

Throws:

java.io.IOException