OSID - osid.billing.batch.EntryPeer Service Interface Definition

Interface	osid.billing.batch.EntryPeer
Implements	`osid.OsidCapsule`
Description	An interface for the peers of the `Entry` relationship.
Method	getCustomerId
Description	Gets the `Id` of the customer.
Return	`osid.id.Id`	the `Customer` `Id`
Compliance	`mandatory`	This method must be implemented.
Method	getItemId
Description	Gets the `Id` of the item.
Return	`osid.id.Id`	the `Item` `Id`
Compliance	`mandatory`	This method must be implemented.
Method	getPeriodId
Description	Gets the `Id` of the period.
Return	`osid.id.Id`	the `Period` `Id`
Compliance	`mandatory`	This method must be implemented.