org.geotools.feature

Class DefaultFeatureCollection

Object

DefaultFeatureCollection

All Implemented Interfaces:

Iterable<SimpleFeature>, Collection<SimpleFeature>, SimpleFeatureCollection, FeatureCollection<SimpleFeatureType,SimpleFeature>

Direct Known Subclasses:

GMLFeatureCollection

public class DefaultFeatureCollection
extends Object
implements SimpleFeatureCollection, Collection<SimpleFeature>

A basic implementation of SimpleFeatureCollection which use a TreeMap for its internal storage.

This should be considered a MemoryFeatureCollection.

Author:

Ian Schneider

Field Summary

Fields

Modifier and Type	Field and Description
protected String	id id used when serialized to gml
protected static Logger	LOGGER
protected SimpleFeatureType	schema

Constructor Summary

Constructors

Constructor and Description
DefaultFeatureCollection() Default implementation of Feature collection.
DefaultFeatureCollection(FeatureCollection<SimpleFeatureType,SimpleFeature> collection) Used to stage content in memory.
DefaultFeatureCollection(String id) Used to create a feature collection to stage content in memory.
DefaultFeatureCollection(String id, SimpleFeatureType memberType) Used to create a feature collection to stage content in memory.

Method Summary

Modifier and Type	Method and Description
void	accepts(FeatureVisitor visitor, ProgressListener progress) Visit the contents of a feature collection.
boolean	add(SimpleFeature o) Ensures that this collection contains the specified element (optional operation).
protected boolean	add(SimpleFeature feature, boolean fire)
boolean	addAll(Collection<? extends SimpleFeature> collection) Adds all of the elements in the specified collection to this collection (optional operation).
boolean	addAll(FeatureCollection<?,?> collection)
void	clear() Removes all of the elements from this collection (optional operation).
void	close(FeatureIterator<SimpleFeature> close)
SimpleFeatureCollection	collection()
boolean	contains(Object o) Returns true if this collection contains the specified element.
boolean	containsAll(Collection<?> collection) Test for collection membership.
SimpleFeatureIterator	features() Gets a SimpleFeatureIterator of this feature collection.
Set	fids() Optimization time ... grab the fid set so other can quickly test membership during removeAll/retainAll implementations.
ReferencedEnvelope	getBounds() Gets the bounding box for the features in this feature collection.
int	getCount()
String	getID() ID used when serializing to GML
SimpleFeatureType	getSchema() The schema for the child feature members of this collection.
boolean	isEmpty() Returns true if this collection contains no elements.
Iterator<SimpleFeature>	iterator() Returns an iterator over the elements in this collection.
void	purge()
FeatureReader<SimpleFeatureType,SimpleFeature>	reader()
boolean	remove(Object o) Removes a single instance of the specified element from this collection, if it is present (optional operation).
boolean	removeAll(Collection<?> collection) Removes all this collection's elements that are also contained in the specified collection (optional operation).
boolean	retainAll(Collection<?> collection) Retains only the elements in this collection that are contained in the specified collection (optional operation).
int	size() Returns the number of elements in this collection.
SimpleFeatureCollection	sort(SortBy order) Construct a sorted view of this content.
SimpleFeatureCollection	subCollection(Filter filter) Will return an optimized subCollection based on access to the origional MemoryFeatureCollection.
Object[]	toArray() Returns an array containing all of the elements in this collection.
<T> T[]	toArray(T[] a) Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array.
void	validate()

Methods inherited from class Object

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

Methods inherited from interface Collection

equals, hashCode, parallelStream, removeIf, spliterator, stream

Methods inherited from interface Iterable

forEach

Field Detail

LOGGER

protected static Logger LOGGER

id

protected String id

id used when serialized to gml

schema

protected SimpleFeatureType schema

Constructor Detail

DefaultFeatureCollection

public DefaultFeatureCollection()

Default implementation of Feature collection.

feature type determined by the first feature added.

DefaultFeatureCollection

public DefaultFeatureCollection(FeatureCollection<SimpleFeatureType,SimpleFeature> collection)

Used to stage content in memory.

Client code is encouraged to use DataUtilities.collection( collection )

Parameters:

collection - SimpleFeatureCollection to copy into memory

DefaultFeatureCollection

public DefaultFeatureCollection(String id)

Used to create a feature collection to stage content in memory.

The feature type will be determined by the first feature added.

Parameters:

id - may be null ... feature id

DefaultFeatureCollection

public DefaultFeatureCollection(String id,
                                SimpleFeatureType memberType)

Used to create a feature collection to stage content in memory.

Parameters:

id - may be null ... feature id

memberType - optional, may be null

Method Detail

getBounds

public ReferencedEnvelope getBounds()

Gets the bounding box for the features in this feature collection.

Specified by:

getBounds in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

the envelope of the geometries contained by this feature collection.

add

public boolean add(SimpleFeature o)

Ensures that this collection contains the specified element (optional operation). Returns true if this collection changed as a result of the call. (Returns false if this collection does not permit duplicates and already contains the specified element.)

Collections that support this operation may place limitations on what elements may be added to this collection. In particular, some collections will refuse to add null elements, and others will impose restrictions on the type of elements that may be added. Collection classes should clearly specify in their documentation any restrictions on what elements may be added.

If a collection refuses to add a particular element for any reason other than that it already contains the element, it must throw an exception (rather than returning false). This preserves the invariant that a collection always contains the specified element after this call returns.

Specified by:

add in interface Collection<SimpleFeature>

Parameters:

o - element whose presence in this collection is to be ensured.

Returns:

true if this collection changed as a result of the call

add

protected boolean add(SimpleFeature feature,
                      boolean fire)

addAll

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

Adds all of the elements in the specified collection to this collection (optional operation). The behavior of this operation is undefined if the specified collection is modified while the operation is in progress. (This implies that the behavior of this call is undefined if the specified collection is this collection, and this collection is nonempty.)

Specified by:

addAll in interface Collection<SimpleFeature>

Parameters:

collection - elements to be inserted into this collection.

Returns:

true if this collection changed as a result of the call

See Also:

Collection.add(Object)

addAll

public boolean addAll(FeatureCollection<?,?> collection)

clear

public void clear()

Removes all of the elements from this collection (optional operation). This collection will be empty after this method returns unless it throws an exception.

Specified by:

clear in interface Collection<SimpleFeature>

contains

public boolean contains(Object o)

Returns true if this collection contains the specified element. More formally, returns true if and only if this collection contains at least one element e such that (o==null ? e==null : o.equals(e)).

Specified by:

contains in interface Collection<SimpleFeature>

Specified by:

contains in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Parameters:

o - element whose presence in this collection is to be tested.

Returns:

true if this collection contains the specified element

See Also:

Collection.contains(Object)

containsAll

public boolean containsAll(Collection<?> collection)

Test for collection membership.

Specified by:

containsAll in interface Collection<SimpleFeature>

Specified by:

containsAll in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

true if collection is completly covered

See Also:

Collection.containsAll(Collection)

isEmpty

public boolean isEmpty()

Returns true if this collection contains no elements.

Specified by:

isEmpty in interface Collection<SimpleFeature>

Specified by:

isEmpty in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

true if this collection contains no elements

iterator

public Iterator<SimpleFeature> iterator()

Returns an iterator over the elements in this collection. There are no guarantees concerning the order in which the elements are returned (unless this collection is an instance of some class that provides a guarantee).

Specified by:

iterator in interface Iterable<SimpleFeature>

Specified by:

iterator in interface Collection<SimpleFeature>

Returns:

an Iterator over the elements in this collection

features

public SimpleFeatureIterator features()

Gets a SimpleFeatureIterator of this feature collection. This allows iteration without having to cast.

Specified by:

features in interface SimpleFeatureCollection

Specified by:

features in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

the SimpleFeatureIterator for this collection.

remove

public boolean remove(Object o)

Removes a single instance of the specified element from this collection, if it is present (optional operation). More formally, removes an element e such that (o==null ? e==null : o.equals(e)), if this collection contains one or more such elements. Returns true if this collection contained the specified element (or equivalently, if this collection changed as a result of the call).

Specified by:

remove in interface Collection<SimpleFeature>

Parameters:

o - element to be removed from this collection, if present.

Returns:

true if this collection changed as a result of the call

removeAll

public boolean removeAll(Collection<?> collection)

Removes all this collection's elements that are also contained in the specified collection (optional operation). After this call returns, this collection will contain no elements in common with the specified collection.

Specified by:

removeAll in interface Collection<SimpleFeature>

Parameters:

collection - elements to be removed from this collection.

Returns:

true if this collection changed as a result of the call

See Also:

remove(Object), contains(Object)

retainAll

public boolean retainAll(Collection<?> collection)

Retains only the elements in this collection that are contained in the specified collection (optional operation). In other words, removes from this collection all of its elements that are not contained in the specified collection.

Specified by:

retainAll in interface Collection<SimpleFeature>

Parameters:

collection - elements to be retained in this collection.

Returns:

true if this collection changed as a result of the call

See Also:

remove(Object), contains(Object)

size

public int size()

Returns the number of elements in this collection. If this collection contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.

Specified by:

size in interface Collection<SimpleFeature>

Specified by:

size in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

the number of elements in this collection

See Also:

Collection.size()

toArray

public Object[] toArray()

Returns an array containing all of the elements in this collection. If the collection makes any guarantees as to what order its elements are returned by its iterator, this method must return the elements in the same order.

The returned array will be "safe" in that no references to it are maintained by this collection. (In other words, this method must allocate a new array even if this collection is backed by an array). The caller is thus free to modify the returned array.

This method acts as bridge between array-based and collection-based APIs.

Specified by:

toArray in interface Collection<SimpleFeature>

Specified by:

toArray in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Returns:

an array containing all of the elements in this collection

See Also:

Collection.toArray()

toArray

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

Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array. If the collection fits in the specified array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the specified array and the size of this collection.

If this collection fits in the specified array with room to spare (i.e., the array has more elements than this collection), the element in the array immediately following the end of the collection is set to null. This is useful in determining the length of this collection only if the caller knows that this collection does not contain any null elements.)

If this collection makes any guarantees as to what order its elements are returned by its iterator, this method must return the elements in the same order.

Like the toArray method, this method acts as bridge between array-based and collection-based APIs. Further, this method allows precise control over the runtime type of the output array, and may, under certain circumstances, be used to save allocation costs

Suppose l is a List known to contain only strings. The following code can be used to dump the list into a newly allocated array of String:

     String[] x = (String[]) v.toArray(new String[0]);
 

Note that toArray(new Object[0]) is identical in function to toArray().

Specified by:

toArray in interface Collection<SimpleFeature>

Specified by:

toArray in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Parameters:

a - the array into which the elements of this collection are to be stored, if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose.

Returns:

an array containing the elements of this collection

See Also:

Collection.toArray(Object[])

close

public void close(FeatureIterator<SimpleFeature> close)

reader

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

Throws:

IOException

getCount

public int getCount()
             throws IOException

Throws:

IOException

collection

public SimpleFeatureCollection collection()
                                   throws IOException

Throws:

IOException

fids

public Set fids()

Optimization time ... grab the fid set so other can quickly test membership during removeAll/retainAll implementations.

Returns:

Set of fids.

accepts

public void accepts(FeatureVisitor visitor,
                    ProgressListener progress)
             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.

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

Throws:

IOException

subCollection

public SimpleFeatureCollection subCollection(Filter filter)

Will return an optimized subCollection based on access to the origional MemoryFeatureCollection.

This method is intended in a manner similar to subList, example use: collection.subCollection( myFilter ).clear()

Specified by:

subCollection in interface SimpleFeatureCollection

Specified by:

subCollection in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Parameters:

filter - Filter used to determine sub collection.

Returns:

SimpleFeatureCollection identified as subset.

Since:

GeoTools 2.2, Filter 1.1

See Also:

FeatureList

sort

public SimpleFeatureCollection sort(SortBy order)

Construct a sorted view of this content.

Sorts may be combined togther in a stable fashion, in congruence with the Filter 1.1 specification.

This method should also be able to handle GeoTools specific sorting through detecting order as a SortBy2 instance.

Specified by:

sort in interface SimpleFeatureCollection

Specified by:

sort in interface FeatureCollection<SimpleFeatureType,SimpleFeature>

Parameters:

order - Filter 1.1 SortBy Construction of a Sort

Returns:

FeatureList sorted according to provided order

Since:

GeoTools 2.2, Filter 1.1

purge

public void purge()

validate

public void validate()

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