OSID - osid.metering.UtilityHierarchySession Service Interface Definition

Interface	osid.metering.UtilityHierarchySession
Implements	`osid.OsidSession`
Description	This session defines methods for traversing a hierarchy of `Utility` objects. Each node in the hierarchy is a unique `Utility.` The hierarchy may be traversed recursively to establish the tree structure through `getParentUtilities()` and `getChildUtilities().` To relate these `Ids` to another OSID, `getUtilityNodes()` can be used for retrievals that can be used for bulk lookups in other OSIDs. Any `Utility` available in the Utility 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 `getParentUtilities()` or `getChildUtilities()` 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: utility elements may be silently omitted or re-ordered plenary view: provides a complete set or is an error condition
Method	getUtilityHierarchyId
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	getUtilityHierarchy
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	canAccessUtilityHierarchy
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 hierrachy traversal operations to unauthorized users.
Return	`boolean`		`false` if hierarchy traversal methods are not authorized, `true` otherwise
Compliance	`mandatory`		This method must be implemented.
Method	useComparativeUtilityView
Description	The returns from the utility 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	usePlenaryUtilityView
Description	A complete view of the `Utility` 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	getRootUtilityIds
Description	Gets the root utility `Ids` in this hierarchy.
Return	`osid.id.IdList`		the root utility `Ids`
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getRootUtilities
Description	Gets the root utilities in the utility hierarchy. A node with no parents is an orphan. While all utility `Ids` are known to the hierarchy, an orphan does not appear in the hierarchy unless explicitly added as a root node or child of another node.
Return	`osid.metering.UtilityList`		the root utilities
Errors	OPERATION_FAILED		unable to complete request
Errors	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method is must be implemented.
Method	hasParentUtilities
Description	Tests if the `Utility` has any parents.
Parameters	`osid.id.Id`	`utilityId`	the `Id` of a utility
Return	`boolean`		`true` if the utility has parents, `false` otherwise
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`utilityId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isParentOfUtility
Description	Tests if an `Id` is a direct parent of a utility.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`utilityId`	the `Id` of a utility
Return	`boolean`		`true` if this `id` is a parent of `utilityId,` `false` otherwise
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`id` or `utilityId` 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	getParentUtilityIds
Description	Gets the parent `Ids` of the given utility.
Parameters	`osid.id.Id`	`utilityId`	the `Id` of a utility
Return	`osid.id.IdList`		the parent `Ids` of the utility
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`utilityId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getParentUtilities
Description	Gets the parent utilities of the given `id.`
Parameters	`osid.id.Id`	`utilityId`	the `Id` of the `Utility` to query
Return	`osid.metering.UtilityList`		the parent utilities of the `id`
Errors	NOT_FOUND		a `Utility` identified by `Id is` not found
	NULL_ARGUMENT		`utilityId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isAncestorOfUtility
Description	Tests if an `Id` is an ancestor of a utility.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`utilityId`	the `Id` of a utility
Return	`boolean`		`true` if this `id` is an ancestor of `utility,` `false` otherwise
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`id` or `utilityId` 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	hasChildUtilities
Description	Tests if a utility has any children.
Parameters	`osid.id.Id`	`utilityId`	the `Id` of a utility
Return	`boolean`		`true` if the `utilityId` has children, `false` otherwise
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`utilityId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isChildOfUtility
Description	Tests if a utility is a direct child of another.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`utilityId`	the `Id` of a utility
Return	`boolean`		`true` if the `id` is a child of `utilityId,` `false` otherwise
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`id` or `utilityId` 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	getChildUtilityIds
Description	Gets the child `Ids` of the given utility.
Parameters	`osid.id.Id`	`utilityId`	the `Id` to query
Return	`osid.id.IdList`		the children of the utility
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`utilityId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getChildUtilities
Description	Gets the child utilities of the given `id.`
Parameters	`osid.id.Id`	`utilityId`	the `Id` of the `Utility` to query
Return	`osid.metering.UtilityList`		the child utilities of the `id`
Errors	NOT_FOUND		a `Utility` identified by `Id is` not found
	NULL_ARGUMENT		`utilityId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	isDescendantOfUtility
Description	Tests if an `Id` is a descendant of a utility.
Parameters	`osid.id.Id`	`id`	an `Id`
Parameters	`osid.id.Id`	`utilityId`	the `Id` of a utility
Return	`boolean`		`true` if the `id` is a descendant of the `utilityId,` `false` otherwise
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`id` or `utilityId` 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	getUtilityNodeIds
Description	Gets a portion of the hierarchy for the given utility.
Parameters	`osid.id.Id`	`utilityId`	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 utility node
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`utilityId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.
Method	getUtilityNodes
Description	Gets a portion of the hierarchy for the given utility.
Parameters	`osid.id.Id`	`utilityId`	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.metering.UtilityNode`		a utility node
Errors	NOT_FOUND		`utilityId` is not found
	NULL_ARGUMENT		`utilityId` is `null`
	OPERATION_FAILED		unable to complete request
	PERMISSION_DENIED		authorization failure
Compliance	`mandatory`		This method must be implemented.