Package net.ssehub.easy.reasoning.core.reasoner

All classes and interfaces needed to implement a reasoner.

How to write a reasoner: Create an Eclipse Plugin project with Activator (even if "empty"). Add org.eclipse.equinox.ds to the required plugins and org.osgi.service.component to the imported packages as your reasoner will be linked using OSGi descriptive services (DS) to the reasoner core.

See: Description

Interface Summary

Interface	Description
ConstraintList.IModificationListener	A listener to be informed if the underlying list changes.
IChainingReasoner	A specialized interface for reasoners, which, in principle, can be chained, i.e., composed to a chain of reasoners, passing along results and configurations.
IMeasurementKey	Base type for measurement keys.
IReasoner	General interface for reasoner, which can be registered to the ReasonerRegistry.
IReasonerInterceptor	An initial reasoner interceptor to be informed about the reasoning process in detail.
IReasonerMessage	Defines a message for internally sending signals among reasoners.
IReasonerMessage.IType	Defines the type of message types.
IReasonerRegistry	Public interface for this reasoner registry capable of handling multiple reasoners.
ReasonerConfiguration.IAdditionalInformationLogger	Describes an information logger.

Class Summary

Class	Description
AnnotationAssignmentConstraint	Reasoner specific constraint type indicating a Constraint.Type.ANNOTATION_ASSIGNMENT constraint.
AttachedConstraint	Implements a constraint with attached object (fixed and Constraint.Type#USUAL type).
AttributesCheckVisitor	A visitor for checking frozen values for all variables which correspond to a given (temporary) assignment of attribute values.
AttributeValues	Stores attributes and their assigned values as an additional information to be considered while reasoning.
CommentResourceVisitor	A visitor turning (partial) IVML elements into more or less explainable strings based on a given CommentResource.
ConstraintBase	Implements the constraint base, a combination of linked list and map in order to quickly store, retrieve and delete constraints to be evaluated.
ConstraintList	Implements a constraint list.
ConstraintList.Node	The node type in a linked constraint base.
ConstraintVariableConstraint	Reasoner specific constraint type indicating a Constraint.Type.CONSTRAINT.
DefaultConstraint	Reasoner specific constraint type indicating a Constraint.Type.DEFAULT constraint.
DelegatingReasonerInstance	Provides a default implementation for reasoner instances by delegating the respective calls to a given delegate reasoner.
EvaluationResult	A specific reasoning result for evaluations of presence conditions.
EvaluationResult.EvaluationPair	Defines a pair of a constraint and its evaluation result.
FileUpgrader	An upgrader for file input locations.
IUpgrader	Defines the interface to an installation upgrade mechanism.
Message	Part of the ReasoningResult class, expressing on error/warning of a complete ReasoningResult.
ReasonerConfiguration	Describes the configuration to be passed via the ReasonerFrontend to the individual reasoners.
ReasonerDescriptor	Represents descriptive information about a reasoner.
ReasonerInterceptorAdaptor	Default empty implementation.
ReasoningErrorCodes	Specifies to witch kind of error belongs failed constraint in the message generated by the reasoner.
ReasoningResult	Result of (one) reasoning step.
TypedConstraint	Reasoner specific constraint type indicating a typed constraint, e.g., a default constraint or a constraint originating from a constraint variable.
ValueCreationResult	Denotes the result of creating a value of an IVML variable through the reasoner considering the relevant constraints.
ZipUpgrader	An upgrader for zip and file input locations.

Enum Summary

Enum	Description
EvaluationResult.ConstraintEvaluationResult	Denotes the possible results of a constraint evaluation.
GeneralMeasures	General reasoner measures.
GeneralReasonerCapabilities	Defines general reasoner capabilities.
IReasonerMessage.Type	Defines basic message types.
Message.SuggestionType	Defines supported suggestion types.
ReasoningOperation	Specifies which kind of reasoning should be performed by the reasoner.

Exception Summary

Exception	Description
AttributeException	A specific exception which may occur when assigning values to attributes.

Package net.ssehub.easy.reasoning.core.reasoner Description

All classes and interfaces needed to implement a reasoner.

How to write a reasoner:

• Create an Eclipse Plugin project with Activator (even if "empty").
• Add org.eclipse.equinox.ds to the required plugins and org.osgi.service.component to the imported packages as your reasoner will be linked using OSGi descriptive services (DS) to the reasoner core. As in our case the automatic registering via references in DS turned out to be instable, we will combine the automatic initialization capabilities with hand-crafted code.
• Implement IReasoner, the interface which represents an individual reasoner. Provide the reasoner with an appropriate instance of ReasonerDescriptor which is used to describe the license of the reasoner as well as additional information such as a URL to download licensed parts.
• Add the following methods to the class implementing IReasoner: protected void activate(org.osgi.service.component.ComponentContext context){ ReasonerFrontend.getInstance().getRegistry().register(this); } protected void deactivate(org.osgi.service.component.ComponentContext context){ ReasonerFrontend.getInstance().getRegistry().unregister(this); } Upon creation of your reasoner class the activate method will be called and it will register your instance with the reasoner core.
• Create a folder named OSGI-INF and put an XML file with the following contents into the new folder (let's call that file reasoner.xml). <?xml version="1.0" encoding="UTF-8"?&rt; <scr:component xmlns:scr="http://www.osgi.org/xmlns/scr/v1.1.0" immediate="true" name="<your descriptive name&rt;"&rt; <implementation class="<your class name&rt;"/&rt; <service&rt; <provide interface="de.uni_hildesheim.sse.reasoning.core.reasoner.IReasoner"/&rt; </service&rt; </scr:component&rt;
• Link the XML file to the manifest by adding Service-Component: OSGI-INF/reasoner.xml (i.e. your specific name).
• While refactoring your code please note that Eclipse typically does not consider the names in the XML file, i.e. they have to be adjusted manually if required.
• For debugging output please specify -Dequinox.ds.debug=true -Dequinox.ds.print=true as JVM parameter.