OSID - osid.ontology.SubjectHierarchySession Service Interface Definition

Interface	osid.ontology.SubjectHierarchySession
Implements	`osid.OsidSession`
Used By	`osid.ontology.OntologyManager`
Used By	`osid.ontology.OntologyProxyManager`
Description	This session defines methods for traversing a hierarchy of `Subject` objects. Each node in the hierarchy is a unique `Subject`. The hierarchy may be traversed recursively to establish the tree structure through `getSubjectNodes()`. To relate these `Ids` to another OSID, `getAncestorSubjects()` and `getDescendantSubjects()` can be used for retrievals that can be used for bulk lookups in other OSIDs. Any `Subject` available in the Ontology OSID is known to this hierarchy but does not appear in the hierarchy traversal until added as a root node or a child of another node. A user may not be authorized to traverse the entire hierarchy. Parts of the hierarchy may be made invisible through omission from the returns of `getParentSubjects()` or `getChildSubjects()` in lieu of a `PERMISSION_DENIED` error that may disrupt the traversal through authorized pathways. This session defines views that offer differing behaviors when retrieving multiple objects. comparative view: subject elements may be silently omitted or re-ordered plenary view: provides a complete set or is an error condition
Method	getSubjectHierarchyId
Description	Gets the hierarchy `Id` associated with this session.
Return	`osid.id.Id`		the hierarchy `Id` associated with this session
Compliance	`mandatory`		This method must be implemented.
Method	getSubjectHierarchy
Description	Gets the hierarchy associated with this session.
Return	`osid.hierarchy.Hierarchy`		the hierarchy associated with this session
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	canAccessSubjectHierarchy
Description	Tests if this user can perform hierarchy queries. A return of true does not guarantee successful authorization. A return of false indicates that it is known all methods in this session will result in a `PERMISSION_DENIED`. This is intended as a hint to an application that may opt not to offer traversal operations.
Return	`boolean`		`false` if hierarchy traversal methods are not authorized, `true` otherwise
Compliance	`mandatory`		This method must be implemented.
Method	useComparativeSubjectView
Description	The returns from the subject methods may omit or translate elements based on this session, such as authorization, and not result in an error. This view is used when greater interoperability is desired at the expense of precision.
Compliance	`mandatory`		This method is must be implemented.
Method	usePlenarySubjectView
Description	A complete view of the `Hierarchy` returns is desired. Methods will return what is requested or result in an error. This view is used when greater precision is desired at the expense of interoperability.
Compliance	`mandatory`		This method is must be implemented.
Method	getRootSubjectIds
Description	Gets the root subject `Ids` in this hierarchy.
Return	`osid.id.IdList`		the root subject `Ids`
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getRootSubjects
Description	Gets the root subjects in this subject hierarchy.
Return	`osid.ontology.SubjectList`		the root subjects
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method is must be implemented.
Method	hasParentSubjects
Description	Tests if the `Subject` has any parents.
Parameters	`osid.id.Id`	`subjectId`	the `Id` of a subject
Return	`boolean`		`true` if the subject has parents, `false` otherwise
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isParentOfSubject
Description	Tests if an `Id` is a direct parent of a subject.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`subjectId`	the `Id` of a subject
Return	`boolean`		`true` if this `id` is a parent of `subjectId`, `false` otherwise
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`id` or `subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Provider Notes	If `id` not found return `false`.
Method	getParentSubjectIds
Description	Gets the parent Ids of the given subject.
Parameters	`osid.id.Id`	`subjectId`	the `Id` of a subject
Return	`osid.id.IdList`		the parent `Ids` of the subject
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getParentSubjects
Description	Gets the parents of the given subject.
Parameters	`osid.id.Id`	`subjectId`	the `Id` of a subject
Return	`osid.ontology.SubjectList`		the parents of the subject
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isAncestorOfSubject
Description	Tests if an `Id` is an ancestor of a subject.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`subjectId`	the `Id` of a subject
Return	`boolean`		`true` if this `id` is an ancestor of `subjectId`, `false` otherwise
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`id` or `subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Provider Notes	If `id` not found return `false`.
Method	hasChildSubjects
Description	Tests if a subject has any children.
Parameters	`osid.id.Id`	`subjectId`	the `Id` of a subject
Return	`boolean`		`true` if the `subjectId` has children, `false` otherwise
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isChildOfSubject
Description	Tests if a subject is a direct child of another.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`subjectId`	the `Id` of a subject
Return	`boolean`		`true` if the `id` is a child of `subjectId`, `false` otherwise
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`id` or `subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Provider Notes	If `id` not found return `false`.
Method	getChildSubjectIds
Description	Gets the child `Ids` of the given subject.
Parameters	`osid.id.Id`	`subjectId`	the `Id` to query
Return	`osid.id.IdList`		the children of the subject
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getChildSubjects
Description	Gets the children of the given subject.
Parameters	`osid.id.Id`	`subjectId`	the `Id` to query
Return	`osid.ontology.SubjectList`		the children of the subject
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isDescendantOfSubject
Description	Tests if an `Id` is a descendant of a subject.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`subjectId`	the `Id` of a subject
Return	`boolean`		`true` if the `id` is a descendant of the `subjectId`, `false` otherwise
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`id` or `subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Provider Notes	If `id` is not found return `false`.
Method	getSubjectNodeIds
Description	Gets a portion of the hierarchy for the given subject.
Parameters	`osid.id.Id`	`subjectId`	the `Id` to query
	`cardinal`	`ancestorLevels`	the maximum number of ancestor levels to include. A value of 0 returns no parents in the node.
	`cardinal`	`descendantLevels`	the maximum number of descendant levels to include. A value of 0 returns no children in the node.
	`boolean`	`includeSiblings`	`true` to include the siblings of the given node, `false` to omit the siblings
Return	`osid.hierarchy.Node`		a subject node
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getSubjectNodes
Description	Gets a portion of the hierarchy for the given subject.
Parameters	`osid.id.Id`	`subjectId`	the `Id` to query
	`cardinal`	`ancestorLevels`	the maximum number of ancestor levels to include. A value of 0 returns no parents in the node.
	`cardinal`	`descendantLevels`	the maximum number of descendant levels to include. A value of 0 returns no children in the node.
	`boolean`	`includeSiblings`	`true` to include the siblings of the given node, `false` to omit the siblings
Return	`osid.ontology.SubjectNode`		a subject node
Errors	NOT_FOUND		`subjectId` is not found
	NULL_ARGUMENT		`subjectId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.