org.biojava.utils

Class AbstractChangeable

java.lang.Object

org.biojava.utils.AbstractChangeable

All Implemented Interfaces:

Changeable

Direct Known Subclasses:

AbiTraceRenderer, AbstractAlphabet, AbstractAnnotation, AbstractBeadRenderer, AbstractBioEntryDB, AbstractCrossOverFunction, AbstractDistribution, AbstractFeatureHolder, AbstractGeneticAlgorithm, AbstractMutationFunction, AbstractOrganism, AbstractOrthologueSet, AbstractOrthoPairSet, AbstractPopulation, AbstractSequenceDB, AbstractSymbol, AbstractSymbolList, AbstractTaxon, AbstractTerm, BasicFeatureRenderer, BioSQLSequenceDB, CrosshairRenderer, DummySequence, FeatureBlockSequenceRenderer, FeatureLabelRenderer, FeatureTypes.RepositoryImpl, GFF3Record.Impl, IndexedCount, LabelledSequenceRenderer, LazyFeatureHolder, MergeAnnotation, MultiLineRenderer, NewSimpleAssembly, OffsetRulerRenderer, Ontology.Impl, OntologyTerm.Impl, OverlayAnnotation, OverlayRendererWrapper, PairDistribution, PairwiseDiagonalRenderer, PairwiseFilteringRenderer, PairwiseOverlayRenderer, SequenceDBSearchHit, SequenceDBSearchResult, SequenceDBSearchSubHit, SequenceRendererWrapper, SimpleAssembly, SimpleBioEntry, SimpleBioEntryRelationship, SimpleCodonPref, SimpleComment, SimpleComparableOntology, SimpleComparableTerm, SimpleComparableTriple, SimpleDocRef, SimpleEmissionState, SimpleFeature, SimpleHomology, SimpleLabelRenderer, SimpleMarkovModel, SimpleNamespace, SimpleNCBITaxon, SimpleNote, SimpleRankedCrossRef, SimpleRankedDocRef, SimpleRichAnnotation, SimpleRichFeature, SimpleRichFeatureRelationship, SimpleRichLocation, SimpleSeqSimilaritySearchHit, SimpleSeqSimilaritySearchResult, SimpleSeqSimilaritySearchSubHit, SimpleSequence, SixFrameRenderer, SixFrameZiggyRenderer, StackedFeatureRenderer, TickFeatureRenderer, TranslatedDistribution, WebSequenceDB, WMAsMM, ZiggyFeatureRenderer

public abstract class AbstractChangeable
extends Object
implements Changeable

Useful base-class for objects implementing Changeable

Author:

Matthew Pocock, Thomas Down, George Waldon - private lock on synchronization

Constructor Summary

Constructors

Constructor and Description
AbstractChangeable()

Method Summary

Methods

Modifier and Type	Method and Description
void	addChangeListener(ChangeListener cl) Add a listener that will be informed of all changes.
void	addChangeListener(ChangeListener cl, ChangeType ct) Add a listener that will be informed of changes of a given type.
protected ChangeSupport	generateChangeSupport() Called the first time a ChangeSupport object is needed.
protected ChangeSupport	getChangeSupport(ChangeType ct) Called to retrieve the ChangeSupport for this object.
protected boolean	hasListeners() Deprecated. use hasListeners(ChangeType) if at all possible
protected boolean	hasListeners(ChangeType ct) Discover if we have listeners registered for a particular change type.
boolean	isUnchanging(ChangeType ct) A particular ChangeType can never be raised by this Changeable.
void	removeChangeListener(ChangeListener cl) Remove a listener that was interested in all types of changes.
void	removeChangeListener(ChangeListener cl, ChangeType ct) Remove a listener that was interested in a specific types of changes.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractChangeable

public AbstractChangeable()

Method Detail

hasListeners

protected boolean hasListeners()

Deprecated. use hasListeners(ChangeType) if at all possible

Discover if we have any listeners registered.

Returns:

true if there is at least one listener

hasListeners

protected boolean hasListeners(ChangeType ct)

Discover if we have listeners registered for a particular change type.

Parameters:

ct - the ChangeType we are interested in

Returns:

true if there is at least one listener

generateChangeSupport

protected ChangeSupport generateChangeSupport()

Called the first time a ChangeSupport object is needed. Override this if you want to set the Unchanging set on the ChangeSupport, or if you want to install listeners on other objects when the change system is initialized.

Since:

1.3

getChangeSupport

protected ChangeSupport getChangeSupport(ChangeType ct)

Called to retrieve the ChangeSupport for this object.

Your implementation of this method should have the following structure:

 ChangeSupport cs = super.getChangeSupport(ct);

 if(someForwarder == null && ct.isMatching(SomeInterface.SomeChangeType)) {
   someForwarder = new ChangeForwarder(...

   this.stateVariable.addChangeListener(someForwarder, VariableInterface.AChange);
 }

 return cs;
 

It is usual for the forwarding listeners (someForwarder in this example) to be transient and lazily instantiated. Be sure to register & unregister the forwarder in the code that does the ChangeEvent handling in setter methods.

addChangeListener

public final void addChangeListener(ChangeListener cl)

Description copied from interface: Changeable

Add a listener that will be informed of all changes.

Specified by:

addChangeListener in interface Changeable

Parameters:

cl - the ChangeListener to add

addChangeListener

public final void addChangeListener(ChangeListener cl,
                     ChangeType ct)

Description copied from interface: Changeable

Add a listener that will be informed of changes of a given type.

Specified by:

addChangeListener in interface Changeable

Parameters:

cl - the ChangeListener

ct - the ChangeType it is to be informed of

removeChangeListener

public final void removeChangeListener(ChangeListener cl)

Description copied from interface: Changeable

Remove a listener that was interested in all types of changes.

Specified by:

removeChangeListener in interface Changeable

Parameters:

cl - a ChangeListener to remove

removeChangeListener

public final void removeChangeListener(ChangeListener cl,
                        ChangeType ct)

Description copied from interface: Changeable

Remove a listener that was interested in a specific types of changes.

Specified by:

removeChangeListener in interface Changeable

Parameters:

cl - a ChangeListener to remove

ct - the ChangeType that it was interested in

isUnchanging

public final boolean isUnchanging(ChangeType ct)

Description copied from interface: Changeable

A particular ChangeType can never be raised by this Changeable.

If this returns true, then it is guaranteed that change events of this type (and all child types) can never under any circumstances be fired by this Changeable instance. If it returns false, that does not mean that this type of event will or even can be raised, but that it is worth registering listeners incase.

Specified by:

isUnchanging in interface Changeable

Parameters:

ct - the ChangeType to check

Returns:

true if ChangeEvents of this type are guaranteed to never be fired