org.geotools.data.collection
Class SpatialIndexFeatureCollection

Object
  SpatialIndexFeatureCollection

All Implemented Interfaces:

SimpleFeatureCollection, FeatureCollection<SimpleFeatureType,SimpleFeature>

public class SpatialIndexFeatureCollection
extends Object
implements SimpleFeatureCollection

FeatureCollection used to stage information for display using a SpatialIndex.

Please note that this feature collection cannot be modified after the spatial index is created.

Author:

Jody

Field Summary

protected STRtree	index SpatialIndex holding the contents of the FeatureCollection
protected List<CollectionListener>	listeners Listeners
protected SimpleFeatureType	schema

Constructor Summary

SpatialIndexFeatureCollection()

SpatialIndexFeatureCollection(SimpleFeatureCollection copy)

SpatialIndexFeatureCollection(SimpleFeatureType schema)

Method Summary

void	accepts(FeatureVisitor visitor, ProgressListener listener) Visit the contents of a feature collection.
boolean	add(SimpleFeature feature) Add object to this collection.
boolean	addAll(Collection<? extends SimpleFeature> collection) Add all the objects to the collection.
boolean	addAll(FeatureCollection<? extends SimpleFeatureType,? extends SimpleFeature> collection)
void	addListener(CollectionListener listener) Adds a listener for collection events.
void	clear()
void	close(FeatureIterator<SimpleFeature> close) Clean up after any resources associated with this FeatureIterator in a manner similar to JDO collections.
void	close(Iterator<SimpleFeature> close) Clean up after any resources associated with this itterator in a manner similar to JDO collections.
boolean	contains(Object obj)
boolean	containsAll(Collection<?> collection)
SimpleFeatureIterator	features() Obtain a FeatureIterator of the Features within this collection.
protected void	fire(SimpleFeature[] features, int eventType)
ReferencedEnvelope	getBounds() Get the total bounds of this collection which is calculated by doing a union of the bounds of each feature inside of it
String	getID() ID used when serializing to GML
SimpleFeatureType	getSchema() The schema for the child feature members of this collection.
boolean	isEmpty()
Iterator<SimpleFeature>	iterator() An iterator over this collection, which must be closed after use.
void	purge() Close any outstanding resources released by this resources.
boolean	remove(Object o)
boolean	removeAll(Collection<?> c)
void	removeListener(CollectionListener listener) Removes a listener for collection events.
boolean	retainAll(Collection<?> c)
int	size() Will build the STRtree index if required.
SimpleFeatureCollection	sort(SortBy order) Obtained sorted contents.
SimpleFeatureCollection	subCollection(Filter filter) SimpleFeatureCollection "view" indicated by provided filter.
Object[]	toArray()
<O> O[]	toArray(O[] array)

Methods inherited from class Object

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

Field Detail

index

protected STRtree index

SpatialIndex holding the contents of the FeatureCollection

schema

protected SimpleFeatureType schema

listeners

protected List<CollectionListener> listeners

Listeners

Constructor Detail

SpatialIndexFeatureCollection

public SpatialIndexFeatureCollection()

SpatialIndexFeatureCollection

public SpatialIndexFeatureCollection(SimpleFeatureType schema)

SpatialIndexFeatureCollection

public SpatialIndexFeatureCollection(SimpleFeatureCollection copy)
                              throws IOException

Throws:

IOException

Method Detail

addListener

public void addListener(CollectionListener listener)
                 throws NullPointerException

Description copied from interface: FeatureCollection

Adds a listener for collection events.

When this collection is backed by live data the event notification will follow the guidelines outlined by FeatureListner.

Specified by:

addListener in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Parameters:

listener - The listener to add

Throws:

NullPointerException - If the listener is null.

removeListener

public void removeListener(CollectionListener listener)
                    throws NullPointerException

Description copied from interface: FeatureCollection

Removes a listener for collection events.

Specified by:

removeListener in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Parameters:

listener - The listener to remove

Throws:

NullPointerException - If the listener is null.

fire

protected void fire(SimpleFeature[] features,
                    int eventType)

features

public SimpleFeatureIterator features()

Description copied from interface: FeatureCollection

Obtain a FeatureIterator of the Features within this collection.

The implementation of Collection must adhere to the rules of fail-fast concurrent modification. In addition (to allow for resource backed collections, the close( Iterator ) method must be called.

This is almost equivalent to:

• a Type-Safe call to: getAttribute(getFeatureType().getAttributeType(0).getName()).iterator();.
• A Java 5:Iterator<Feature>

Example (safe) use:

 FeatureIterator iterator=collection.features();
 try {
     while( iterator.hasNext()  ){
          Feature feature = iterator.next();
          System.out.println( feature.getID() );
     }
 }
 finally {
     collection.close( iterator );
 }
 

GML Note: The contents of this iterator are considered to be defined by featureMember tags (and/or the single allowed FeatureMembers tag). Please see getFeatureType for more details.

Specified by:

features in interface SimpleFeatureCollection

Specified by:

features in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

A FeatureIterator.

sort

public SimpleFeatureCollection sort(SortBy order)

Description copied from interface: FeatureCollection

Obtained sorted contents.

This method may not be supported by all implementations, consider the use of FeatureSource.features( Query ).

Specified by:

sort in interface SimpleFeatureCollection

Specified by:

sort in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Parameters:

order - Sort order

Returns:

FeatureCollection sorted in the indicated order

subCollection

public SimpleFeatureCollection subCollection(Filter filter)

Description copied from interface: FeatureCollection

SimpleFeatureCollection "view" indicated by provided filter.

The contents of the returned SimpleFeatureCollection are determined by applying the provider Filter to the entire contents of this FeatureCollection. The result is "live" and modifications will be shared.

This method is used cut down on the number of filter based methods required for a useful SimpleFeatureCollection construct. The FeatureCollections returned really should be considered as a temporary "view" used to control the range of a removeAll, or modify operation.

Example Use:

 collection.subCollection( filter ).clear();
 

The above recommended use is agreement with the Collections API precident of List.subList( start, end ).

The results of subCollection:

• are to be considered unordered
• may be an ordered FeatureList if requested when sortBy is indicated

Specified by:

subCollection in interface SimpleFeatureCollection

Specified by:

subCollection in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

SimpleFeatureCollection identified as subset.

See Also:

FeatureList

accepts

public void accepts(FeatureVisitor visitor,
                    ProgressListener listener)
             throws IOException

Description copied from interface: FeatureCollection

Visit the contents of a feature collection.

The order of traversal is dependent on the FeatureCollection implementation; some collections are able to make efficient use of an internal index in order to quickly visit features located in the same region.

Specified by:

accepts in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Parameters:

visitor - Closure applied to each feature in turn.

listener - Used to report progress, may be used to interrupt the operation

Throws:

IOException

add

public boolean add(SimpleFeature feature)

Description copied from interface: FeatureCollection

Add object to this collection.

This method is often not impelmented for collections produced as the result of a query.

Specified by:

add in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

true of the element was added

See Also:

Collection.add(Object)

addAll

public boolean addAll(Collection<? extends SimpleFeature> collection)

Description copied from interface: FeatureCollection

Add all the objects to the collection.

This method is often not implemented for collections produced as the results of a query.

Specified by:

addAll in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.addAll(Collection)

addAll

public boolean addAll(FeatureCollection<? extends SimpleFeatureType,? extends SimpleFeature> collection)

Specified by:

addAll in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

FeatureCollection.addAll(Collection)

clear

public void clear()

Specified by:

clear in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.clear()

close

public void close(FeatureIterator<SimpleFeature> close)

Description copied from interface: FeatureCollection

Clean up after any resources associated with this FeatureIterator in a manner similar to JDO collections.

Example (safe) use:

 Iterator iterator = collection.iterator();
 try {
     for( Iterator i=collection.iterator(); i.hasNext();){
          Feature feature = i.hasNext();
          System.out.println( feature.getID() );
     }
 }
 finally {
     collection.close( iterator );
 }
 

Specified by:

close in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

close

public void close(Iterator<SimpleFeature> close)

Description copied from interface: FeatureCollection

Clean up after any resources associated with this itterator in a manner similar to JDO collections.

Example (safe) use:

 Iterator iterator = collection.iterator();
 try {
     for( Iterator i=collection.iterator(); i.hasNext();){
          Feature feature = (Feature) i.hasNext();
          System.out.println( feature.getID() );
     }
 }
 finally {
     collection.close( iterator );
 }
 

Specified by:

close in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

contains

public boolean contains(Object obj)

Specified by:

contains in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.contains(Object)

containsAll

public boolean containsAll(Collection<?> collection)

Specified by:

containsAll in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.containsAll(Collection)

getBounds

public ReferencedEnvelope getBounds()

Description copied from interface: FeatureCollection

Get the total bounds of this collection which is calculated by doing a union of the bounds of each feature inside of it

Specified by:

getBounds in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

An Envelope containing the total bounds of this collection.

getID

public String getID()

Description copied from interface: FeatureCollection

ID used when serializing to GML

Specified by:

getID in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

getSchema

public SimpleFeatureType getSchema()

Description copied from interface: FeatureCollection

The schema for the child feature members of this collection.

Represents the most general FeatureType in common to all the features in this collection.

• For a collection backed by a shapefiles (or database tables) the FeatureType returned by getSchema() will complete describe each and every child in the collection.
• For mixed content FeatureCollections you will need to check the FeatureType of each Feature as it is retrived from the collection
• The degenerate case returns the "_Feature" FeatureType, where the only thing known is that the contents are Features.

Specified by:

getSchema in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

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

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.isEmpty()

iterator

public Iterator<SimpleFeature> iterator()

Description copied from interface: FeatureCollection

An iterator over this collection, which must be closed after use.

Collection is not guaranteed to be ordered in any manner.

The implementation of Collection must adhere to the rules of fail-fast concurrent modification. In addition (to allow for resource backed collections, the close( Iterator ) method must be called.

Example (safe) use:

 Iterator iterator = collection.iterator();
 try {
     while( iterator.hasNext();){
          Feature feature = (Feature) iterator.hasNext();
          System.out.println( feature.getID() );
     }
 }
 finally {
     collection.close( iterator );
 }
 

Specified by:

iterator in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

Iterator

purge

public void purge()

Description copied from interface: FeatureCollection

Close any outstanding resources released by this resources.

This method should be used with great caution, it is however available to allow the use of the ResourceCollection with algorthims that are unaware of the need to close iterators after use.

Example of using a normal Collections utility method:

 Collections.sort( collection );
 collection.purge();
 

Specified by:

purge in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

remove

public boolean remove(Object o)

Specified by:

remove in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.remove(Object)

removeAll

public boolean removeAll(Collection<?> c)

Specified by:

removeAll in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.removeAll(Collection)

retainAll

public boolean retainAll(Collection<?> c)

Specified by:

retainAll in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.retainAll(Collection)

size

public int size()

Will build the STRtree index if required.

Specified by:

size in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.size()

toArray

public Object[] toArray()

Specified by:

toArray in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.toArray()

toArray

public <O> O[] toArray(O[] array)

Specified by:

toArray in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

See Also:

Collection.toArray(Object[])