org.geotools.referencing.factory
Class DeferredAuthorityFactory

Object
  extended by AbstractFactory
      extended by ReferencingFactory
          extended by AbstractAuthorityFactory
              extended by BufferedAuthorityFactory
                  extended by DeferredAuthorityFactory
All Implemented Interfaces:
RegisterableService, BufferedFactory, Factory, OptionalFactory, AuthorityFactory
Direct Known Subclasses:
FactoryUsingWKT, LongitudeFirstEpsgDecorator, LongitudeFirstFactory, ThreadedEpsgFactory

public abstract class DeferredAuthorityFactory
extends BufferedAuthorityFactory
implements OptionalFactory

A buffered authority factory which will defer the creation of a backing store until when first needed. This approach allow to etablish a connection to a database (for example) only when first needed. In addition, the backing store can be automatically disposed after a timeout and recreated when needed again.

Since:
2.1
Author:
Martin Desruisseaux (IRD)
Module:
modules/library/referencing (gt-referencing.jar)

Field Summary
 
Fields inherited from class ReferencingFactory
LOGGER
 
Fields inherited from class AbstractFactory
hints, MAXIMUM_PRIORITY, MINIMUM_PRIORITY, NORMAL_PRIORITY, priority
 
Constructor Summary
protected DeferredAuthorityFactory(Hints userHints, int priority)
          Constructs an instance without initial backing store.
protected DeferredAuthorityFactory(Hints userHints, int priority, int maxStrongReferences)
          Constructs an instance without initial backing store.
 
Method Summary
protected  boolean canDisposeBackingStore(AbstractAuthorityFactory backingStore)
          Returns true if the backing store can be disposed now.
protected abstract  AbstractAuthorityFactory createBackingStore()
          Creates the backing store authority factory.
 void dispose()
          Releases resources immediately instead of waiting for the garbage collector.
 boolean isAvailable()
          Returns true if this factory is available.
 boolean isConnected()
          Returns true if this deferred factory is connected to its backing store.
 void setTimeout(long delay)
          Set a timer for disposing the backing store after the specified amount of milliseconds of inactivity.
 
Methods inherited from class BufferedAuthorityFactory
createCartesianCS, createCompoundCRS, createCoordinateOperation, createCoordinateReferenceSystem, createCoordinateSystem, createCoordinateSystemAxis, createCylindricalCS, createDatum, createDerivedCRS, createEllipsoid, createEllipsoidalCS, createEngineeringCRS, createEngineeringDatum, createExtent, createFromCoordinateReferenceSystemCodes, createGeocentricCRS, createGeodeticDatum, createGeographicCRS, createImageCRS, createImageDatum, createObject, createOperationMethod, createParameterDescriptor, createPolarCS, createPrimeMeridian, createProjectedCRS, createSphericalCS, createTemporalCRS, createTemporalDatum, createTimeCS, createUnit, createVerticalCRS, createVerticalCS, createVerticalDatum, getAuthority, getAuthorityCodes, getBackingStoreDescription, getDescriptionText, getIdentifiedObjectFinder, getVendor
 
Methods inherited from class AbstractAuthorityFactory
noSuchAuthorityCode, trimAuthority
 
Methods inherited from class ReferencingFactory
ensureNonNull
 
Methods inherited from class AbstractFactory
addImplementationHints, equals, getImplementationHints, getPriority, hashCode, onDeregistration, onRegistration, toString
 
Methods inherited from class Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface Factory
getImplementationHints
 

Constructor Detail

DeferredAuthorityFactory

protected DeferredAuthorityFactory(Hints userHints,
                                   int priority)
Constructs an instance without initial backing store. Subclasses are responsible for creating an appropriate backing store when the createBackingStore() method is invoked.

Parameters:
userHints - An optional set of hints, or null if none.
priority - The priority for this factory, as a number between MINIMUM_PRIORITY and MAXIMUM_PRIORITY inclusive.
Since:
2.2
See Also:
createBackingStore()

DeferredAuthorityFactory

protected DeferredAuthorityFactory(Hints userHints,
                                   int priority,
                                   int maxStrongReferences)
Constructs an instance without initial backing store. Subclasses are responsible for creating an appropriate backing store when the createBackingStore() method is invoked.

Parameters:
userHints - An optional set of hints, or null if none.
priority - The priority for this factory, as a number between MINIMUM_PRIORITY and MAXIMUM_PRIORITY inclusive.
maxStrongReferences - The maximum number of objects to keep by strong reference.
Since:
2.2
See Also:
createBackingStore()
Method Detail

isAvailable

public boolean isAvailable()
Returns true if this factory is available. The default implementation returns false if createBackingStore() throws an exception.

Specified by:
isAvailable in interface OptionalFactory

createBackingStore

protected abstract AbstractAuthorityFactory createBackingStore()
                                                        throws FactoryException
Creates the backing store authority factory. This method is invoked the first time a createXXX(...) method is invoked.

Returns:
The backing store to uses in createXXX(...) methods.
Throws:
FactoryNotFoundException - if the backing store has not been found.
FactoryException - if the creation of backing store failed for an other reason.

isConnected

public boolean isConnected()
Returns true if this deferred factory is connected to its backing store. This method returns false if no createFoo method has been invoked, if the backing store has been automatically disposed after the timeout or if this factoy has been disposed.


setTimeout

public void setTimeout(long delay)
Set a timer for disposing the backing store after the specified amount of milliseconds of inactivity. The createBackingStore() method will be responsible for creating a new backing store when needed. Note that the backing store disposal can be vetoed if canDisposeBackingStore(org.geotools.referencing.factory.AbstractAuthorityFactory) returns false.

Parameters:
delay - The minimal delay before to close the backing store. This delay is very approximative. The backing store will not be closed before, but may take as much as twice that time before to be closed.

canDisposeBackingStore

protected boolean canDisposeBackingStore(AbstractAuthorityFactory backingStore)
Returns true if the backing store can be disposed now. This method is invoked automatically after the amount of time specified by setTimeout(long) if the factory were not used during that time. The default implementation always returns true. Subclasses should override this method and returns false if they want to prevent the backing store disposal under some circonstances.

Parameters:
backingStore - The backing store in process of being disposed.

dispose

public void dispose()
             throws FactoryException
Releases resources immediately instead of waiting for the garbage collector. This method disposes the backing store regardeless of canDisposeBackingStore(org.geotools.referencing.factory.AbstractAuthorityFactory) value.

Overrides:
dispose in class BufferedAuthorityFactory
Throws:
FactoryException - if an error occured while disposing the factory.


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