org.eclipse.incquery.runtime.base.api

Interface NavigationHelper

All Known Implementing Classes:

NavigationHelperImpl

public interface NavigationHelper

Using an index of the EMF model, this interface exposes useful query functionality, such as:

• Getting all the (direct or descendant) instances of a given EClass
• Inverse navigation along arbitrary EReference instances (heterogenous paths too)
• Finding model elements by attribute value (i.e. inverse navigation along EAttribute)
• Querying instances of given data types, or structural features.

As queries are served from an index, results are always instantaneous.

Such indices will be built on an EMF model rooted at an EObject, Resource or ResourceSet. The boundaries of the model are defined by the containment (sub)tree. The indices will be maintained incrementally on changes to the model; these updates can also be observed by registering listeners.

One of the options is to build indices in wildcard mode, meaning that all EClasses, EDataTypes, EReferences and EAttributes are indexed. This is convenient, but comes at a high memory cost. To save memory, one can disable wildcard mode and manually register those EClasses, EDataTypes, EReferences and EAttributes that should be indexed.

Another choice is whether to build indices in dynamic EMF mode, meaning that types are identified by the String IDs that are ultimately derived from the nsURI of the EPackage. Multiple types with the same ID are treated as the same. This is useful if dynamic EMF is used, where there can be multiple copies (instantiations) of the same EPackage, representing essentially the same metamodel. If one disables dynamic EMF mode, an error is logged if duplicate EPackages with the same nsURI are encountered.

Note that none of the defined query methods return null upon empty result sets. All query methods return either a copy of the result sets (where EStructuralFeature.Setting is instantiated) or an unmodifiable collection of the result view.

Instantiate using IncQueryBaseFactory

Author:

Tamas Szabo

Method Summary

Modifier and Type	Method and Description
void	addBaseIndexChangeListener(EMFBaseIndexChangeListener listener) Adds a coarse-grained listener that will be invoked after the NavigationHelper index or the underlying model is changed.
void	addDataTypeListener(java.util.Collection<org.eclipse.emf.ecore.EDataType> types, DataTypeListener listener) The given listener will be notified from now on whenever instances the given EDataTypes are added to or removed from the model.
void	addFeatureListener(java.util.Collection<? extends org.eclipse.emf.ecore.EStructuralFeature> features, FeatureListener listener) The given listener will be notified from now on whenever instances the given EStructuralFeatures are added to or removed from the model.
boolean	addIndexingErrorListener(IEMFIndexingErrorListener listener) Adds a listener for internal errors in the index.
void	addInstanceListener(java.util.Collection<org.eclipse.emf.ecore.EClass> classes, InstanceListener listener) The given listener will be notified from now on whenever instances the given EClasses (and any of their subtypes) are added to or removed from the model.
boolean	addLightweightEObjectObserver(LightweightEObjectObserver observer, org.eclipse.emf.ecore.EObject observedObject) Register a lightweight observer that is notified if the value of any feature of the given EObject changes.
void	addRoot(org.eclipse.emf.common.notify.Notifier emfRoot) Adds an additional EMF model root.
void	cheapMoveTo(org.eclipse.emf.ecore.EObject element, org.eclipse.emf.ecore.EObject parent, org.eclipse.emf.ecore.EReference containmentFeature) Moves an EObject (along with its entire containment subtree) within the containment hierarchy of the EMF model.
<T extends org.eclipse.emf.ecore.EObject> void	cheapMoveTo(T element, org.eclipse.emf.common.util.EList<T> targetContainmentReferenceList) Moves an EObject (along with its entire containment subtree) within the containment hierarchy of the EMF model.
<V> V	coalesceTraversals(java.util.concurrent.Callable<V> callable) The given callback will be executed, and all model traversals and index registrations will be delayed until the execution is done.
void	dispose() Call this method to dispose the NavigationHelper.
java.util.Set<org.eclipse.emf.ecore.EStructuralFeature.Setting>	findByAttributeValue(java.lang.Object value) For a given attribute value value, find each EAttribute and host EObject such that this attribute of the the host object takes the given value.
java.util.Set<org.eclipse.emf.ecore.EStructuralFeature.Setting>	findByAttributeValue(java.lang.Object value, java.util.Collection<org.eclipse.emf.ecore.EAttribute> attributes) For given attributes and an attribute value value, find each host EObject such that any of these attributes of the the host object takes the given value.
java.util.Set<org.eclipse.emf.ecore.EObject>	findByAttributeValue(java.lang.Object value, org.eclipse.emf.ecore.EAttribute attribute) Find all EObjects for which the given attribute takes the given value.
java.util.Set<org.eclipse.emf.ecore.EObject>	findByFeatureValue(java.lang.Object value, org.eclipse.emf.ecore.EStructuralFeature feature) Find all source EObjects for which the given feature points to / takes the given value.
java.util.Set<org.eclipse.emf.ecore.EClass>	getAllCurrentClasses() Returns all EClasses that currently have direct instances cached by the index.
java.util.Set<org.eclipse.emf.ecore.EObject>	getAllInstances(org.eclipse.emf.ecore.EClass clazz) Get the all EObject instances of the given EClass.
java.util.Set<java.lang.Object>	getDataTypeInstances(org.eclipse.emf.ecore.EDataType type) Returns the set of instances for the given EDataType that can be found in the model.
java.util.Set<org.eclipse.emf.ecore.EObject>	getDirectInstances(org.eclipse.emf.ecore.EClass clazz) Get the direct EObject instances of the given EClass.
java.util.Map<org.eclipse.emf.ecore.EObject,java.util.Set<java.lang.Object>>	getFeatureInstances(org.eclipse.emf.ecore.EStructuralFeature feature) Find all value assignment instances of the given EStructuralFeature in the form of a host EObject -> value(s) multimap.
java.util.Set<java.lang.Object>	getFeatureTargets(org.eclipse.emf.ecore.EObject source, org.eclipse.emf.ecore.EStructuralFeature feature) Find all Objects that are the target of the EStructuralFeature feature from the given source EObject.
java.util.Set<org.eclipse.emf.ecore.EObject>	getHoldersOfFeature(org.eclipse.emf.ecore.EStructuralFeature feature) Returns those host EObjects that have a non-null value for the given feature (at least one, in case of multi-valued references).
java.util.Set<org.eclipse.emf.ecore.EStructuralFeature.Setting>	getInverseReferences(org.eclipse.emf.ecore.EObject target) For a given EObject target, find each EReference and source EObject such that this reference (list) of the the host object points to the given target object.
java.util.Set<org.eclipse.emf.ecore.EStructuralFeature.Setting>	getInverseReferences(org.eclipse.emf.ecore.EObject target, java.util.Collection<org.eclipse.emf.ecore.EReference> references) For given references and an EObject target, find each source EObject such that any of these references of the the source object points to the given target object.
java.util.Set<org.eclipse.emf.ecore.EObject>	getInverseReferences(org.eclipse.emf.ecore.EObject target, org.eclipse.emf.ecore.EReference reference) Find all source EObjects for which the given reference points to the given target object.
java.util.Set<org.eclipse.emf.ecore.EObject>	getReferenceValues(org.eclipse.emf.ecore.EObject source, org.eclipse.emf.ecore.EReference reference) Find all EObjects that are the target of the EReference reference from the given source EObject.
boolean	isCoalescing() Examines whether execution is currently in the callable block of an invocation of {#link coalesceTraversals(Callable)}.
boolean	isInDynamicEMFMode() Indicates whether indexing is performed in dynamic EMF mode, i.e.
boolean	isInWildcardMode() Indicates whether indexing is performed in wildcard mode, where every aspect of the EMF model is automatically indexed.
void	processAllFeatureInstances(org.eclipse.emf.ecore.EStructuralFeature feature, IEStructuralFeatureProcessor processor) Traverses all instances of a selected feature stored in the base index, and allows executing a custom function on it.
void	processAllInstances(org.eclipse.emf.ecore.EClass type, IEClassifierProcessor.IEClassProcessor processor) Traverses all direct instances of a selected class stored in the base index, and allows executing a custom function on it.
void	processDataTypeInstances(org.eclipse.emf.ecore.EDataType type, IEClassifierProcessor.IEDataTypeProcessor processor) Traverses all instances of a selected data type stored in the base index, and allows executing a custom function on it.
void	processDirectInstances(org.eclipse.emf.ecore.EClass type, IEClassifierProcessor.IEClassProcessor processor) Traverses all direct instances of a selected class stored in the base index, and allows executing a custom function on it.
void	registerEClasses(java.util.Set<org.eclipse.emf.ecore.EClass> classes) Manually turns on indexing for the given classes (indexing of other classes are unaffected).
void	registerEDataTypes(java.util.Set<org.eclipse.emf.ecore.EDataType> dataTypes) Manually turns on indexing for the given data types (indexing of other features are unaffected).
void	registerEStructuralFeatures(java.util.Set<? extends org.eclipse.emf.ecore.EStructuralFeature> features) Manually turns on indexing for the given features (indexing of other features are unaffected).
void	registerObservedTypes(java.util.Set<org.eclipse.emf.ecore.EClass> classes, java.util.Set<org.eclipse.emf.ecore.EDataType> dataTypes, java.util.Set<? extends org.eclipse.emf.ecore.EStructuralFeature> features) Manually turns on indexing for the given types (indexing of others are unaffected).
void	removeBaseIndexChangeListener(EMFBaseIndexChangeListener listener) Removes a registered listener.
void	removeDataTypeListener(java.util.Collection<org.eclipse.emf.ecore.EDataType> types, DataTypeListener listener) Unregisters a data type listener for the given types.
void	removeFeatureListener(java.util.Collection<? extends org.eclipse.emf.ecore.EStructuralFeature> features, FeatureListener listener) Unregisters a feature listener for the given features.
boolean	removeIndexingErrorListener(IEMFIndexingErrorListener listener) Removes a listener for internal errors in the index
void	removeInstanceListener(java.util.Collection<org.eclipse.emf.ecore.EClass> classes, InstanceListener listener) Unregisters an instance listener for the given classes.
boolean	removeLightweightEObjectObserver(LightweightEObjectObserver observer, org.eclipse.emf.ecore.EObject observedObject) Unregisters a lightweight observer for the given EObject.
void	resampleDerivedFeatures() Updates the value of indexed derived features that are not well-behaving.
java.lang.Object	toCanonicalValueRepresentation(java.lang.Object value) Returns the internal, canonicalized implementation of an attribute value.
void	unregisterEClasses(java.util.Set<org.eclipse.emf.ecore.EClass> classes) Manually turns off indexing for the given classes (indexing of other classes are unaffected).
void	unregisterEDataTypes(java.util.Set<org.eclipse.emf.ecore.EDataType> dataTypes) Manually turns off indexing for the given data types (indexing of other data types are unaffected).
void	unregisterEStructuralFeatures(java.util.Set<? extends org.eclipse.emf.ecore.EStructuralFeature> features) Manually turns off indexing for the given features (indexing of other features are unaffected).
void	unregisterObservedTypes(java.util.Set<org.eclipse.emf.ecore.EClass> classes, java.util.Set<org.eclipse.emf.ecore.EDataType> dataTypes, java.util.Set<? extends org.eclipse.emf.ecore.EStructuralFeature> features) Manually turns off indexing for the given types (indexing of others are unaffected).

Method Detail

isInWildcardMode

boolean isInWildcardMode()

Indicates whether indexing is performed in wildcard mode, where every aspect of the EMF model is automatically indexed.

Returns:

true if everything is indexed, false if manual registration of interesting EClassifiers and EStructuralFeatures is required.

isInDynamicEMFMode

boolean isInDynamicEMFMode()

Indicates whether indexing is performed in dynamic EMF mode, i.e. EPackage nsURI collisions are tolerated and EPackages with the same URI are automatically considered as equal.

Returns:

true if multiple EPackages with the same nsURI are treated as the same, false if an error is logged instead in this case.

findByAttributeValue

java.util.Set<org.eclipse.emf.ecore.EStructuralFeature.Setting> findByAttributeValue(java.lang.Object value)

For a given attribute value value, find each EAttribute and host EObject such that this attribute of the the host object takes the given value. The method will return a set of EStructuralFeature.Settings, one for each such host object - EAttribute - value triplet.

Precondition: Unset / null attribute values are not indexed, so value!=null

Precondition: Will only find those EAttributes that have already been registered using registerEStructuralFeatures(Set), unless running in wildcard mode (see isInWildcardMode()).

Parameters:

value - the value of the attribute

Returns:

a set of EStructuralFeature.Settings, one for each EObject and EAttribute that have the given value

See Also:

findByAttributeValue(Object)

findByAttributeValue

java.util.Set<org.eclipse.emf.ecore.EStructuralFeature.Setting> findByAttributeValue(java.lang.Object value,
                                                                                     java.util.Collection<org.eclipse.emf.ecore.EAttribute> attributes)

For given attributes and an attribute value value, find each host EObject such that any of these attributes of the the host object takes the given value. The method will return a set of EStructuralFeature.Settings, one for each such host object - EAttribute - value triplet.

Precondition: Unset / null attribute values are not indexed, so value!=null

Precondition: Will only find those EAttributes that have already been registered using registerEStructuralFeatures(Set), unless running in wildcard mode (see isInWildcardMode()).

Parameters:

value - the value of the attribute

attributes - the collection of attributes that should take the given value

Returns:

a set of EStructuralFeature.Settings, one for each EObject and attribute that have the given value

findByAttributeValue

java.util.Set<org.eclipse.emf.ecore.EObject> findByAttributeValue(java.lang.Object value,
                                                                  org.eclipse.emf.ecore.EAttribute attribute)

Find all EObjects for which the given attribute takes the given value.

Precondition: Unset / null attribute values are not indexed, so value!=null

Precondition: Results will be returned only if either (a) the EAttribute has already been registered using registerEStructuralFeatures(Set), or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

value - the value of the attribute

attribute - the EAttribute that should take the given value

Returns:

the set of EObjects for which the given attribute has the given value

getDataTypeInstances

java.util.Set<java.lang.Object> getDataTypeInstances(org.eclipse.emf.ecore.EDataType type)

Returns the set of instances for the given EDataType that can be found in the model.

Precondition: Results will be returned only if either (a) the EDataType has already been registered using registerEDataTypes(Set), or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

type - the data type

Returns:

the set of all attribute values found in the model that are of the given data type

getReferenceValues

java.util.Set<org.eclipse.emf.ecore.EObject> getReferenceValues(org.eclipse.emf.ecore.EObject source,
                                                                org.eclipse.emf.ecore.EReference reference)

Find all EObjects that are the target of the EReference reference from the given source EObject.

Unset / null-valued references are not indexed, and will not be included in the results.

Precondition: Results will be returned only if either (a) the reference has already been registered using registerEStructuralFeatures(Set), or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

source - the host object

reference - an EReference of the host object

Returns:

the set of EObjects that the given reference points to, from the given source object

getFeatureTargets

java.util.Set<java.lang.Object> getFeatureTargets(org.eclipse.emf.ecore.EObject source,
                                                  org.eclipse.emf.ecore.EStructuralFeature feature)

Find all Objects that are the target of the EStructuralFeature feature from the given source EObject.

Unset / null-valued features are not indexed, and will not be included in the results.

Precondition: Results will be returned only if either (a) the feature has already been registered, or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

source - the host object

feature - an EStructuralFeature of the host object

Returns:

the set of values that the given feature takes at the given source object

See Also:

getReferenceValues(EObject, EReference)

getFeatureInstances

java.util.Map<org.eclipse.emf.ecore.EObject,java.util.Set<java.lang.Object>> getFeatureInstances(org.eclipse.emf.ecore.EStructuralFeature feature)

Find all value assignment instances of the given EStructuralFeature in the form of a host EObject -> value(s) multimap.

Unset / null-valued features are not indexed, and will not be included in the results.

Precondition: Results will be returned only if either (a) the feature has already been registered, or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

feature - the EStructuralFeature

Returns:

the map from source EObjects to the value(s) of the given feature

getInverseReferences

java.util.Set<org.eclipse.emf.ecore.EStructuralFeature.Setting> getInverseReferences(org.eclipse.emf.ecore.EObject target)

For a given EObject target, find each EReference and source EObject such that this reference (list) of the the host object points to the given target object. The method will return a set of EStructuralFeature.Settings, one for each such source object - EReference - target triplet.

Precondition: Unset / null reference values are not indexed, so target!=null

Precondition: Results will be returned only for those references that have already been registered using registerEStructuralFeatures(Set), or all references if running in wildcard mode (see isInWildcardMode()).

Parameters:

target - the EObject pointed to by the references

Returns:

a set of EStructuralFeature.Settings, one for each source EObject and reference that point to the given target

getInverseReferences

java.util.Set<org.eclipse.emf.ecore.EStructuralFeature.Setting> getInverseReferences(org.eclipse.emf.ecore.EObject target,
                                                                                     java.util.Collection<org.eclipse.emf.ecore.EReference> references)

For given references and an EObject target, find each source EObject such that any of these references of the the source object points to the given target object. The method will return a set of EStructuralFeature.Settings, one for each such source object - EReference - target triplet.

Precondition: Unset / null reference values are not indexed, so target!=null

Precondition: Will only find those EReferences that have already been registered using registerEStructuralFeatures(Set), unless running in wildcard mode (see isInWildcardMode()).

Parameters:

target - the EObject pointed to by the references

references - a set of EReferences pointing to the target

Returns:

a set of EStructuralFeature.Settings, one for each source EObject and reference that point to the given target

getInverseReferences

java.util.Set<org.eclipse.emf.ecore.EObject> getInverseReferences(org.eclipse.emf.ecore.EObject target,
                                                                  org.eclipse.emf.ecore.EReference reference)

Find all source EObjects for which the given reference points to the given target object.

Precondition: Unset / null reference values are not indexed, so target!=null

Precondition: Results will be returned only if either (a) the reference has already been registered using registerEStructuralFeatures(Set), or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

target - the EObject pointed to by the references

reference - an EReference pointing to the target

Returns:

the collection of EObjects for which the given reference points to the given target object

getDirectInstances

java.util.Set<org.eclipse.emf.ecore.EObject> getDirectInstances(org.eclipse.emf.ecore.EClass clazz)

Get the direct EObject instances of the given EClass. Instances of subclasses will be excluded.

Precondition: Results will be returned only if either (a) the EClass (or any superclass) has already been registered using registerEClasses(Set), or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

clazz - an EClass

Returns:

the collection of EObject direct instances of the given EClass (not of subclasses)

See Also:

getAllInstances(EClass)

getAllInstances

java.util.Set<org.eclipse.emf.ecore.EObject> getAllInstances(org.eclipse.emf.ecore.EClass clazz)

Get the all EObject instances of the given EClass. This includes instances of subclasses.

Precondition: Results will be returned only if either (a) the EClass (or any superclass) has already been registered using registerEClasses(Set), or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

clazz - an EClass

Returns:

the collection of EObject instances of the given EClass and any of its subclasses

See Also:

getDirectInstances(EClass)

findByFeatureValue

java.util.Set<org.eclipse.emf.ecore.EObject> findByFeatureValue(java.lang.Object value,
                                                                org.eclipse.emf.ecore.EStructuralFeature feature)

Find all source EObjects for which the given feature points to / takes the given value.

Precondition: Unset / null-valued features are not indexed, so value!=null

Precondition: Results will be returned only if either (a) the feature has already been registered using registerEStructuralFeatures(Set), or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

value - the value of the feature

feature - the feature instance

Returns:

the collection of EObject instances

getHoldersOfFeature

java.util.Set<org.eclipse.emf.ecore.EObject> getHoldersOfFeature(org.eclipse.emf.ecore.EStructuralFeature feature)

Returns those host EObjects that have a non-null value for the given feature (at least one, in case of multi-valued references).

Unset / null-valued features are not indexed, and will not be included in the results.

Precondition: Results will be returned only if either (a) the feature has already been registered using registerEStructuralFeatures(Set), or (b) running in wildcard mode (see isInWildcardMode()).

Parameters:

feature - a structural feature

Returns:

the collection of EObjects that have some value for the given structural feature

dispose

void dispose()

Call this method to dispose the NavigationHelper.

After its disposal, the NavigationHelper will no longer listen to EMF change notifications, and it will be possible to GC it even if the model is retained in memory.

Precondition:

no listeners can be registered at all.

Throws:

java.lang.IllegalStateException - if there are any active listeners

addInstanceListener

void addInstanceListener(java.util.Collection<org.eclipse.emf.ecore.EClass> classes,
                         InstanceListener listener)

The given listener will be notified from now on whenever instances the given EClasses (and any of their subtypes) are added to or removed from the model.

Parameters:

classes - the collection of classes whose instances the listener should be notified of

listener - the listener instance

removeInstanceListener

void removeInstanceListener(java.util.Collection<org.eclipse.emf.ecore.EClass> classes,
                            InstanceListener listener)

Unregisters an instance listener for the given classes.

Parameters:

classes - the collection of classes

listener - the listener instance

addDataTypeListener

void addDataTypeListener(java.util.Collection<org.eclipse.emf.ecore.EDataType> types,
                         DataTypeListener listener)

The given listener will be notified from now on whenever instances the given EDataTypes are added to or removed from the model.

Parameters:

types - the collection of types associated to the listener

listener - the listener instance

removeDataTypeListener

void removeDataTypeListener(java.util.Collection<org.eclipse.emf.ecore.EDataType> types,
                            DataTypeListener listener)

Unregisters a data type listener for the given types.

Parameters:

types - the collection of data types

listener - the listener instance

addFeatureListener

void addFeatureListener(java.util.Collection<? extends org.eclipse.emf.ecore.EStructuralFeature> features,
                        FeatureListener listener)

The given listener will be notified from now on whenever instances the given EStructuralFeatures are added to or removed from the model.

Parameters:

features - the collection of features associated to the listener

listener - the listener instance

removeFeatureListener

void removeFeatureListener(java.util.Collection<? extends org.eclipse.emf.ecore.EStructuralFeature> features,
                           FeatureListener listener)

Unregisters a feature listener for the given features.

Parameters:

listener - the listener instance

features - the collection of features

addLightweightEObjectObserver

boolean addLightweightEObjectObserver(LightweightEObjectObserver observer,
                                      org.eclipse.emf.ecore.EObject observedObject)

Register a lightweight observer that is notified if the value of any feature of the given EObject changes.

Parameters:

observer - the listener instance

observedObject - the observed EObject

Returns:

false if the observer was already attached to the object (call has no effect), true otherwise

removeLightweightEObjectObserver

boolean removeLightweightEObjectObserver(LightweightEObjectObserver observer,
                                         org.eclipse.emf.ecore.EObject observedObject)

Unregisters a lightweight observer for the given EObject.

Parameters:

observer - the listener instance

observedObject - the observed EObject

Returns:

false if the observer has not been previously attached to the object (call has no effect), true otherwise

registerObservedTypes

void registerObservedTypes(java.util.Set<org.eclipse.emf.ecore.EClass> classes,
                           java.util.Set<org.eclipse.emf.ecore.EDataType> dataTypes,
                           java.util.Set<? extends org.eclipse.emf.ecore.EStructuralFeature> features)

Manually turns on indexing for the given types (indexing of others are unaffected). Note that registering new types will result in a single iteration through the whole attached model. Not usable in wildcard mode.

Parameters:

classes - the set of classes to observe (null okay)

dataTypes - the set of data types to observe (null okay)

features - the set of features to observe (null okay)

Throws:

java.lang.IllegalStateException - if in wildcard mode

unregisterObservedTypes

void unregisterObservedTypes(java.util.Set<org.eclipse.emf.ecore.EClass> classes,
                             java.util.Set<org.eclipse.emf.ecore.EDataType> dataTypes,
                             java.util.Set<? extends org.eclipse.emf.ecore.EStructuralFeature> features)

Manually turns off indexing for the given types (indexing of others are unaffected). Note that if the unregistered types are re-registered later, the whole attached model needs to be visited again. Not usable in wildcard mode.

Precondition:

no listeners can be registered for the given types.

Parameters:

classes - the set of classes that will be ignored again from now on (null okay)

dataTypes - the set of data types that will be ignored again from now on (null okay)

features - the set of features that will be ignored again from now on (null okay)

Throws:

java.lang.IllegalStateException - if in wildcard mode, or if there are listeners registered for the given types

registerEStructuralFeatures

void registerEStructuralFeatures(java.util.Set<? extends org.eclipse.emf.ecore.EStructuralFeature> features)

Manually turns on indexing for the given features (indexing of other features are unaffected). Note that registering new features will result in a single iteration through the whole attached model. Not usable in wildcard mode.

Parameters:

features - the set of features to observe

Throws:

java.lang.IllegalStateException - if in wildcard mode

unregisterEStructuralFeatures

void unregisterEStructuralFeatures(java.util.Set<? extends org.eclipse.emf.ecore.EStructuralFeature> features)

Manually turns off indexing for the given features (indexing of other features are unaffected). Note that if the unregistered features are re-registered later, the whole attached model needs to be visited again. Not usable in wildcard mode.

Precondition:

no listeners can be registered for the given features.

Parameters:

features - the set of features that will be ignored again from now on

Throws:

java.lang.IllegalStateException - if in wildcard mode, or if there are listeners registered for the given types

registerEClasses

void registerEClasses(java.util.Set<org.eclipse.emf.ecore.EClass> classes)

Manually turns on indexing for the given classes (indexing of other classes are unaffected). Instances of subclasses will also be indexed. Note that registering new classes will result in a single iteration through the whole attached model. Not usable in wildcard mode.

Parameters:

classes - the set of classes to observe

Throws:

java.lang.IllegalStateException - if in wildcard mode

unregisterEClasses

void unregisterEClasses(java.util.Set<org.eclipse.emf.ecore.EClass> classes)

Manually turns off indexing for the given classes (indexing of other classes are unaffected). Note that if the unregistered classes are re-registered later, the whole attached model needs to be visited again. Not usable in wildcard mode.

Precondition:

no listeners can be registered for the given classes.

Parameters:

classes - the set of classes that will be ignored again from now on

Throws:

java.lang.IllegalStateException - if in wildcard mode, or if there are listeners registered for the given types

registerEDataTypes

void registerEDataTypes(java.util.Set<org.eclipse.emf.ecore.EDataType> dataTypes)

Manually turns on indexing for the given data types (indexing of other features are unaffected). Note that registering new data types will result in a single iteration through the whole attached model. Not usable in wildcard mode.

Parameters:

dataTypes - the set of data types to observe

Throws:

java.lang.IllegalStateException - if in wildcard mode

unregisterEDataTypes

void unregisterEDataTypes(java.util.Set<org.eclipse.emf.ecore.EDataType> dataTypes)

Manually turns off indexing for the given data types (indexing of other data types are unaffected). Note that if the unregistered data types are re-registered later, the whole attached model needs to be visited again. Not usable in wildcard mode.

Precondition:

no listeners can be registered for the given datatypes.

Parameters:

dataTypes - the set of data types that will be ignored again from now on

Throws:

java.lang.IllegalStateException - if in wildcard mode, or if there are listeners registered for the given types

coalesceTraversals

<V> V coalesceTraversals(java.util.concurrent.Callable<V> callable)
                  throws java.lang.reflect.InvocationTargetException

The given callback will be executed, and all model traversals and index registrations will be delayed until the execution is done. If there are any outstanding feature, class or datatype registrations, a single coalesced model traversal will initialize the caches and deliver the notifications.

Parameters:

callable -

Throws:

java.lang.reflect.InvocationTargetException

isCoalescing

boolean isCoalescing()

Examines whether execution is currently in the callable block of an invocation of {#link coalesceTraversals(Callable)}.

addBaseIndexChangeListener

void addBaseIndexChangeListener(EMFBaseIndexChangeListener listener)

Adds a coarse-grained listener that will be invoked after the NavigationHelper index or the underlying model is changed. Can be used e.g. to check model contents. Not intended for general use.

See removeBaseIndexChangeListener(EMFBaseIndexChangeListener)

Parameters:

listener -

removeBaseIndexChangeListener

void removeBaseIndexChangeListener(EMFBaseIndexChangeListener listener)

Removes a registered listener.

See addBaseIndexChangeListener(EMFBaseIndexChangeListener)

Parameters:

listener -

addRoot

void addRoot(org.eclipse.emf.common.notify.Notifier emfRoot)
      throws IncQueryBaseException

Adds an additional EMF model root.

Parameters:

emfRoot -

Throws:

IncQueryBaseException

cheapMoveTo

<T extends org.eclipse.emf.ecore.EObject> void cheapMoveTo(T element,
                                                           org.eclipse.emf.common.util.EList<T> targetContainmentReferenceList)

Moves an EObject (along with its entire containment subtree) within the containment hierarchy of the EMF model. The object will be relocated from the original parent object to a different parent, or a different containment list of the same parent.

When indexing is enabled, such a relocation is costly if performed through normal getters/setters, as the index for the entire subtree is pruned at the old location and reconstructed at the new one. This method provides a workaround to keep the operation cheap.

This method is experimental. Re-entrancy not supported.

Parameters:

element - the eObject to be moved

targetContainmentReferenceList - containment list of the new parent object into which the element has to be moved

cheapMoveTo

void cheapMoveTo(org.eclipse.emf.ecore.EObject element,
                 org.eclipse.emf.ecore.EObject parent,
                 org.eclipse.emf.ecore.EReference containmentFeature)

Moves an EObject (along with its entire containment subtree) within the containment hierarchy of the EMF model. The object will be relocated from the original parent object to a different parent, or a different containment list of the same parent.

When indexing is enabled, such a relocation is costly if performed through normal getters/setters, as the index for the entire subtree is pruned at the old location and reconstructed at the new one. This method provides a workaround to keep the operation cheap.

This method is experimental. Re-entrancy not supported.

Parameters:

element - the eObject to be moved

parent - the new parent object under which the element has to be moved

containmentFeature - the kind of containment reference that should be established between the new parent and the element

processDataTypeInstances

void processDataTypeInstances(org.eclipse.emf.ecore.EDataType type,
                              IEClassifierProcessor.IEDataTypeProcessor processor)

Traverses all instances of a selected data type stored in the base index, and allows executing a custom function on it. There is no guaranteed order in which the processor will be called with the selected features.

Parameters:

type -

processor -

Since:

0.8

processAllInstances

void processAllInstances(org.eclipse.emf.ecore.EClass type,
                         IEClassifierProcessor.IEClassProcessor processor)

Traverses all direct instances of a selected class stored in the base index, and allows executing a custom function on it. There is no guaranteed order in which the processor will be called with the selected features.

Parameters:

type -

processor -

Since:

0.8

processDirectInstances

void processDirectInstances(org.eclipse.emf.ecore.EClass type,
                            IEClassifierProcessor.IEClassProcessor processor)

Traverses all direct instances of a selected class stored in the base index, and allows executing a custom function on it. There is no guaranteed order in which the processor will be called with the selected features.

Parameters:

type -

processor -

Since:

0.8

processAllFeatureInstances

void processAllFeatureInstances(org.eclipse.emf.ecore.EStructuralFeature feature,
                                IEStructuralFeatureProcessor processor)

Traverses all instances of a selected feature stored in the base index, and allows executing a custom function on it. There is no guaranteed order in which the processor will be called with the selected features.

Precondition: Will only find those EAttributes that have already been registered using registerEStructuralFeatures(Set), unless running in wildcard mode (see isInWildcardMode()).

Parameters:

feature -

processor -

getAllCurrentClasses

java.util.Set<org.eclipse.emf.ecore.EClass> getAllCurrentClasses()

Returns all EClasses that currently have direct instances cached by the index.

• Supertypes will not be returned, unless they have direct instances in the model as well.
• If not in wildcard mode, only registered EClasses and their subtypes will be considered.
• Note for advanced users: if a type is represented by multiple EClass objects, one of them is chosen as representative and returned.

resampleDerivedFeatures

void resampleDerivedFeatures()

Updates the value of indexed derived features that are not well-behaving.

addIndexingErrorListener

boolean addIndexingErrorListener(IEMFIndexingErrorListener listener)

Adds a listener for internal errors in the index. A listener can only be added once.

Parameters:

listener -

Since:

0.8

removeIndexingErrorListener

boolean removeIndexingErrorListener(IEMFIndexingErrorListener listener)

Removes a listener for internal errors in the index

Parameters:

listener -

Since:

0.8

toCanonicalValueRepresentation

java.lang.Object toCanonicalValueRepresentation(java.lang.Object value)

Returns the internal, canonicalized implementation of an attribute value.

Behaviour: when in dynamic EMF mode, substitutes enum literals with a canonical version of the enum literal. Otherwise, returns the input.

The canonical enum literal will be guaranteed to be a valid EMF enum literal (Enumerator), and the best effort is made to ensure that it will be the same for all versions of the EEnum, including EEnumLiterals in different versions of ecore packages, as well as Java enums generated from them..

Usage is not required when simply querying the indexed model through the NavigationHelper API, as both method inputs and the results returned are automatically canonicalized in dynamic EMF mode. Using this method is required only if the client wants to do querying/filtering on the results returned, and wants to know what to look for.