org.geotools.data.store

Class MaxFeaturesFeatureCollection<T extends FeatureType,F extends Feature>

Object

DecoratingFeatureCollection<T,F>

MaxFeaturesFeatureCollection<T,F>

All Implemented Interfaces:

FeatureCollection<T,F>

public class MaxFeaturesFeatureCollection<T extends FeatureType,F extends Feature>
extends DecoratingFeatureCollection<T,F>

SimpleFeatureCollection wrapper which limits the number of features returned.

Author:

Justin Deoliveira, The Open Planning Project

Constructor Summary

Constructors

Constructor and Description
MaxFeaturesFeatureCollection(FeatureCollection<T,F> delegate, long max)

Method Summary

Modifier and Type	Method and Description
boolean	containsAll(Collection<?> c)
FeatureIterator<F>	features() Obtain a FeatureIterator of the Features within this FeatureCollection.
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
boolean	isEmpty() Returns true if this feature collection contains no features.
FeatureReader<T,F>	reader()
int	size() Please note this operation may be expensive when working with remote content.
FeatureCollection<T,F>	sort(SortBy order) Obtained sorted contents.
FeatureCollection<T,F>	subCollection(Filter filter) SimpleFeatureCollection "view" indicated by provided filter.
Object[]	toArray()
<O> O[]	toArray(O[] a)

Methods inherited from class DecoratingFeatureCollection

accepts, contains, equals, getID, getSchema, hashCode

Methods inherited from class Object

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

Constructor Detail

MaxFeaturesFeatureCollection

public MaxFeaturesFeatureCollection(FeatureCollection<T,F> delegate,
                                    long max)

Method Detail

reader

public FeatureReader<T,F> reader()
                          throws IOException

Throws:

IOException

features

public FeatureIterator<F> features()

Description copied from interface: FeatureCollection

Obtain a FeatureIterator of the Features within this FeatureCollection.

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

Example use:

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

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 FeatureCollection<T extends FeatureType,F extends Feature>

Overrides:

features in class DecoratingFeatureCollection<T extends FeatureType,F extends Feature>

Returns:

A FeatureIterator.

subCollection

public FeatureCollection<T,F> 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 FeatureCollection<T extends FeatureType,F extends Feature>

Overrides:

subCollection in class DecoratingFeatureCollection<T extends FeatureType,F extends Feature>

Returns:

SimpleFeatureCollection identified as subset.

See Also:

FeatureList

sort

public FeatureCollection<T,F> 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 FeatureCollection<T extends FeatureType,F extends Feature>

Overrides:

sort in class DecoratingFeatureCollection<T extends FeatureType,F extends Feature>

Parameters:

order - Sort order

Returns:

FeatureCollection sorted in the indicated order

size

public int size()

Description copied from interface: FeatureCollection

Please note this operation may be expensive when working with remote content.

Specified by:

size in interface FeatureCollection<T extends FeatureType,F extends Feature>

Overrides:

size in class DecoratingFeatureCollection<T extends FeatureType,F extends Feature>

See Also:

Collection.size()

isEmpty

public boolean isEmpty()

Description copied from interface: FeatureCollection

Returns true if this feature collection contains no features.

Specified by:

isEmpty in interface FeatureCollection<T extends FeatureType,F extends Feature>

Overrides:

isEmpty in class DecoratingFeatureCollection<T extends FeatureType,F extends Feature>

Returns:

true if this collection contains no features

toArray

public Object[] toArray()

Specified by:

toArray in interface FeatureCollection<T extends FeatureType,F extends Feature>

Overrides:

toArray in class DecoratingFeatureCollection<T extends FeatureType,F extends Feature>

See Also:

Collection.toArray()

toArray

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

Specified by:

toArray in interface FeatureCollection<T extends FeatureType,F extends Feature>

Overrides:

toArray in class DecoratingFeatureCollection<T extends FeatureType,F extends Feature>

See Also:

Collection.toArray(Object[])

containsAll

public boolean containsAll(Collection<?> c)

Specified by:

containsAll in interface FeatureCollection<T extends FeatureType,F extends Feature>

Overrides:

containsAll in class DecoratingFeatureCollection<T extends FeatureType,F extends Feature>

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<T extends FeatureType,F extends Feature>

Overrides:

getBounds in class DecoratingFeatureCollection<T extends FeatureType,F extends Feature>

Returns:

An Envelope containing the total bounds of this collection.