org.geotools.referencing.factory

Class IdentifiedObjectSet

Object

AbstractCollection<E>

AbstractSet

IdentifiedObjectSet

All Implemented Interfaces:

Serializable, Iterable, Collection, Set

public class IdentifiedObjectSet
extends AbstractSet
implements Serializable

A lazy set of identified objects. This set creates IdentifiedObjects from authority codes only when first needed. This class is typically used as the set returned by implementations of the createFromCoordinateReferenceSystemCodes method. Deferred creation in this case may have great performance impact since a set may contains about 40 entries (e.g. transformations from "ED50" (EPSG:4230) to "WGS 84" (EPSG:4326)) while some users only want to look for the first entry (e.g. the default AuthorityBackedFactory implementation).

Exception handling

If the underlying factory failed to creates an object because of an unsupported operation method (NoSuchIdentifierException), the exception is logged with the FINE level (because this is a recoverable failure) and the iteration continue. If the operation creation failed for any other kind of reason (FactoryException), then the exception is rethrown as an unchecked BackingStoreException. This default behavior can be changed if a subclass overrides the isRecoverableFailure method.

Serialization

Serialization of this class forces the immediate creation of all identified objects not yet created. The serialized set is disconnected from the underlying factory.

Thread safety

This class is not thread-safe.

Since:

2.2

Author:

Martin Desruisseaux (IRD)

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected AuthorityFactory	factory The factory to use for creating identified objects when first needed.

Constructor Summary

Constructors

Constructor and Description
IdentifiedObjectSet(AuthorityFactory factory) Creates an initially empty set.

Method Summary

Modifier and Type	Method and Description
boolean	add(Object object) Ensures that this collection contains the specified object.
boolean	addAuthorityCode(String code) Ensures that this collection contains an object for the specified authority code.
void	clear() Removes all of the elements from this collection.
boolean	contains(Object object) Returns true if this collection contains the specified object.
protected IdentifiedObject	createObject(String code) Creates an object for the specified authority code.
protected String	getAuthorityCode(IdentifiedObject object) Returns the code to uses as a key for the specified object.
String[]	getAuthorityCodes() Returns the authority code of all objects in this set.
protected boolean	isRecoverableFailure(FactoryException exception) Returns true if the specified exception should be handled as a recoverable failure.
Iterator	iterator() Returns an iterator over the objects in this set.
boolean	remove(Object object) Removes a single instance of the specified element from this collection, if it is present.
boolean	removeAll(Collection collection) Removes from this collection all of its elements that are contained in the specified collection.
void	resolve(int n) Ensures that the n first objects in this set are created.
void	setAuthorityCodes(String... codes) Set the content of this set as an array of authority codes.
int	size() Returns the number of objects available in this set.
protected Object	writeReplace() Returns a serializable copy of this set.

Methods inherited from class AbstractSet

equals, hashCode

Methods inherited from class AbstractCollection

addAll, containsAll, isEmpty, retainAll, toArray, toArray, toString

Methods inherited from class Object

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

Methods inherited from interface Set

addAll, containsAll, isEmpty, retainAll, spliterator, toArray, toArray

Methods inherited from interface Collection

parallelStream, removeIf, stream

Methods inherited from interface Iterable

forEach

Field Detail

factory

protected final AuthorityFactory factory

The factory to use for creating identified objects when first needed.

Constructor Detail

IdentifiedObjectSet

public IdentifiedObjectSet(AuthorityFactory factory)

Creates an initially empty set. The IdentifiedObjects will be created when first needed using the specified factory.

Parameters:

factory - The factory to use for deferred IdentifiedObjects creations.

Method Detail

clear

public void clear()

Removes all of the elements from this collection.

Specified by:

clear in interface Collection

Specified by:

clear in interface Set

Overrides:

clear in class AbstractCollection

size

public int size()

Returns the number of objects available in this set. Note that this number may decrease during the iteration process if the creation of some identified objects failed.

Specified by:

size in interface Collection

Specified by:

size in interface Set

Specified by:

size in class AbstractCollection

addAuthorityCode

public boolean addAuthorityCode(String code)

Ensures that this collection contains an object for the specified authority code. The identified object will be created from the specified code only when first needed. This method returns true if this set changed as a result of this call.

add

public boolean add(Object object)

Ensures that this collection contains the specified object. This set do not allows multiple objects for the same authority code. If this set already contains an object using the same authority code than the specified one, then the old object is replaced by the new one even if the objects are not otherwise identical.

Specified by:

add in interface Collection

Specified by:

add in interface Set

Overrides:

add in class AbstractCollection

contains

public boolean contains(Object object)

Returns true if this collection contains the specified object.

Specified by:

contains in interface Collection

Specified by:

contains in interface Set

Overrides:

contains in class AbstractCollection

remove

public boolean remove(Object object)

Removes a single instance of the specified element from this collection, if it is present.

Specified by:

remove in interface Collection

Specified by:

remove in interface Set

Overrides:

remove in class AbstractCollection

removeAll

public boolean removeAll(Collection collection)

Removes from this collection all of its elements that are contained in the specified collection.

Specified by:

removeAll in interface Collection

Specified by:

removeAll in interface Set

Overrides:

removeAll in class AbstractSet

iterator

public Iterator iterator()

Returns an iterator over the objects in this set. If the iteration encounter any kind of FactoryException other than NoSuchIdentifierException, then the exception will be rethrown as an unchecked BackingStoreException.

Specified by:

iterator in interface Iterable

Specified by:

iterator in interface Collection

Specified by:

iterator in interface Set

Specified by:

iterator in class AbstractCollection

resolve

public void resolve(int n)
             throws FactoryException

Ensures that the n first objects in this set are created. This method is typically invoked after some calls to addAuthorityCode(java.lang.String) in order to make sure that the underlying factory is really capable to create at least one object. FactoryException (except the ones accepted as recoverable failures) are thrown as if they were never wrapped into BackingStoreException.

Parameters:

n - The number of object to resolve. If this number is equals or greater than the set's size, then the creation of all objects is garantee successful.

Throws:

FactoryException - if an object creation failed.

getAuthorityCodes

public String[] getAuthorityCodes()

Returns the authority code of all objects in this set. The returned array contains the codes in iteration order. This method do not trig the creation of any new object.

This method is typically used together with setAuthorityCodes(java.lang.String...) for altering the iteration order on the basis of authority codes.

setAuthorityCodes

public void setAuthorityCodes(String... codes)

Set the content of this set as an array of authority codes. For any code in the given list, this method will preserve the corresponding identified object if it was already created. Other objects will be created only when first needed, as usual in this IdentifiedObjectSet implementation.

This method is typically used together with getAuthorityCodes() for altering the iteration order on the basis of authority codes. If the specified codes array contains the same elements than getAuthorityCodes() in a different order, then this method just set the new ordering.

See Also:

addAuthorityCode(java.lang.String)

getAuthorityCode

protected String getAuthorityCode(IdentifiedObject object)

Returns the code to uses as a key for the specified object. The default implementation returns the code of the first identifier, if any, or the code of theprimary name otherwise. Subclasses may overrides this method if they want to use a different key for this set.

createObject

protected IdentifiedObject createObject(String code)
                                 throws FactoryException

Creates an object for the specified authority code. This method is invoked during the iteration process if an object was not already created. The default implementation invokes factory.createObject(code). Subclasses may override this method if they want to invoke a more specific method.

Throws:

FactoryException

isRecoverableFailure

protected boolean isRecoverableFailure(FactoryException exception)

Returns true if the specified exception should be handled as a recoverable failure. This method is invoked during the iteration process if the factory failed to create some object. If this method returns true for the given exception, then the exception will be logged in the Geotools factory logger with the FINE level. If this method returns false, then the exception will be retrown as a BackingStoreException. The default implementation returns true only for NoSuchIdentifierException (not to be confused with NoSuchAuthorityCodeException).

writeReplace

protected Object writeReplace()
                       throws ObjectStreamException

Returns a serializable copy of this set. This method is invoked automatically during serialization. The serialised set of identified objects is disconnected from the underlying factory.

Throws:

ObjectStreamException