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OSID Specifications
osid package
Version 3.1.0
Interfaceosid.OsidOperator
Implementsosid.OsidEnabler
Description

An OsidOperator is an OsidEnabler that governs the operational status of an Operable. The OsidOperator itself may be active or inactive. An Operable is operational when any applied OsidOperator is active. When all applied OsidOperators are inactive, then the Operable is not operational. If isRequirement() is true, then this OsidOperator must be active regardless of the state of any other applied OsidOperators.

Operables are active or inactive. Operables may change their operational status over time, but if two evaluations occur at the same point in time each of the evaluations should see the same operational status. For example, a bridge can be open or closed, but it cannot be open for one car and closed for another car at the same time. OsidOperators are rules which govern the Operable status over time but OsidOperators do not incorporate context that varies from one perspective to the next. OsidOperators define several built-in dimensions to govern its operational status.
  • effective dates: The OsidEnabler is operational during these dates and evaluated using a date.
  • schedule: The OsidEnabler is operational when the date is occurs on the Schedule and the date is within the effective dates.
  • event: The OsidEnabler is operational when the date occurs within the Event and the date is within the effective dates. Events may be comprised of Schedules and other rules making them discontinuous.
  • cyclic event: The OsidEnabler is operational when the date cccurs within the CyclicEvent and the date is within the effective dates. CyclicEvents may be complex recurring events but also recur from one time period to the next, such as annually.
  • time period: The OsidEnabler is operational during a TimePeriod.
  • cyclic time period: The OsidEnabler is operational during a recurring TimePeriod. For example, any Spring term.