OSID - osid.learning.ObjectiveHierarchySession Service Interface Definition

Interface	osid.learning.ObjectiveHierarchySession
Implements	`osid.OsidSession`
Used By	`osid.learning.LearningManager`
Used By	`osid.learning.LearningProxyManager`
Description	This session defines methods for traversing a hierarchy of `Objectives`. Each node in the hierarchy is a unique `Objective that contains its child objectives`. The hierarchy may be traversed recursively to establish the tree structure through `getParentObjectives()` and `getChildObjectives()`. To relate these `Ids` to another OSID, `getObjectiveNodes()` can be used for retrievals that can be used for bulk lookups in other OSIDs. Any `Objective` available in the Learning 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 `getParentObjectives()` or `getChildObjectives()` 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: objective elements may be silently omitted or re-ordered plenary view: provides a complete set or is an error condition
Method	getObjectiveHierarchyId
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	getObjectiveHierarchy
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	canAccessObjectiveHierarchy
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 an application that may not offer traversal functions to unauthorized users.
Return	`boolean`		`false` if hierarchy traversal methods are not authorized, `true` otherwise
Compliance	`mandatory`		This method must be implemented.
Method	useComparativeObjectiveView
Description	The returns from the objective 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	usePlenaryObjectiveView
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	getRootObjectiveIds
Description	Gets the root objective `Ids` in this hierarchy.
Return	`osid.id.IdList`		the root objective `Ids`
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getRootObjectives
Description	Gets the root objective in this objective hierarchy.
Return	`osid.learning.ObjectiveList`		the root objective
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method is must be implemented.
Method	hasParentObjectives
Description	Tests if the `Objective` has any parents.
Parameters	`osid.id.Id`	`objectiveId`	the `Id` of an objective
Return	`boolean`		`true` if the objective has parents, `false` otherwise
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`objectiveId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isParentOfObjective
Description	Tests if an `Id` is a direct parent of an objective.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`objectiveId`	the `Id` of an objective
Return	`boolean`		`true` if this `id` is a parent of `objectiveId`, `false` otherwise
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`id` or `objectiveId` 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	getParentObjectiveIds
Description	Gets the parent `Ids` of the given objective.
Parameters	`osid.id.Id`	`objectiveId`	the `Id` of an objective
Return	`osid.id.IdList`		the parent `Ids` of the objective
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`objectiveId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getParentObjectives
Description	Gets the parents of the given objective.
Parameters	`osid.id.Id`	`objectiveId`	the `Id` of an objective
Return	`osid.learning.ObjectiveList`		the parents of the objective
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`objectiveId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isAncestorOfObjective
Description	Tests if an `Id` is an ancestor of an objective.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`objectiveId`	the `Id` of an objective
Return	`boolean`		`true` if this `id` is an ancestor of `objectiveId`, `false` otherwise
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`id` or `objectiveId` 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	hasChildObjectives
Description	Tests if an objective has any children.
Parameters	`osid.id.Id`	`objectiveId`	the `Id` of an objective
Return	`boolean`		`true` if the `objectiveId` has children, `false` otherwise
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`objectiveId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isChildOfObjective
Description	Tests if an objective is a direct child of another.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`objectiveId`	the `Id` of an objective
Return	`boolean`		`true` if the `id` is a child of `objectiveId`, `false` otherwise
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`id` or `objectiveId` 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	getChildObjectiveIds
Description	Gets the child `Ids` of the given objective.
Parameters	`osid.id.Id`	`objectiveId`	the `Id` to query
Return	`osid.id.IdList`		the children of the objective
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`objectiveId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getChildObjectives
Description	Gets the children of the given objective.
Parameters	`osid.id.Id`	`objectiveId`	the `Id` to query
Return	`osid.learning.ObjectiveList`		the children of the objective
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`objectiveId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isDescendantOfObjective
Description	Tests if an `Id` is a descendant of an objective.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`objectiveId`	the `Id` of an objective
Return	`boolean`		`true` if the `id` is a descendant of the `objectiveId`, `false` otherwise
Errors	NOT_FOUND		`objectiveId` is not found
	NULL_ARGUMENT		`id` or `objectiveId` 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	getObjectiveNodeIds
Description	Gets a portion of the hierarchy for the given objective.
Parameters	`osid.id.Id`	`objectiveId`	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 catalog node
Errors	NOT_FOUND		`objectiveId` not found
	NULL_ARGUMENT		`objectiveId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getObjectiveNodes
Description	Gets a portion of the hierarchy for the given objective.
Parameters	`osid.id.Id`	`objectiveId`	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.learning.ObjectiveNode`		an objective node
Errors	NOT_FOUND		`objectiveId` not found
	NULL_ARGUMENT		`objectiveId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.