org.ocap.resource.ResourceContentionHandler.html Maven / Gradle / Ivy

A class implementing this interface decides which application shall be allowed to reserve a resource.

An application which has a MonitorAppPermission("handler.resource") may have a class implementing this interface, and may set an instance of it in the ResourceContentionManager. The resolveResourceContention(org.ocap.resource.ResourceUsage, org.ocap.resource.ResourceUsage[]) method decides the how to resolve resource conflicts between the new request and existing resource allocations. See the ResourceContentionManager for the details.

resolveResourceContention

ResourceUsage[] resolveResourceContention(ResourceUsage newRequest,
                                          ResourceUsage[] currentReservations)

This method notifies the ResourceContentionHandler that one to many resource contentions have occurred between one or more applications and system modules, except the Emergency Alert System (EAS) module. EAS system module resource requests SHALL be given the highest priority by the implementation and resource requests by this module SHALL not be reported to the ResourceContentionHandler. In the case of one application, the same application is conflicting with itself and a registered ResourceContentionHandler SHALL be notified in this case.

This method notifies the ResourceContentionHandler that one to many resource contentions have occurred between two or more applications. Each entry in the currentReservations indicates a set of resources reserved by an application for a single activity such as a resource usage by a single service context. There may be multiple entries in this list from a single application. An entry may correspond to a current resource usage or resource reservations for a future activity.

A prioritized array of ResourceUsage instances is returned. The array is in priority order from highest to lowest indicating the priority order to be followed by the implementation while resolving the conflicts. When this method returns the implementation will iterate through each entry in the array in the order of priority, awarding resources as required by the activity represented by the resourceUsage. The ResourceContentionHandler may use information such as Application Priority to prioritize the array of ResourceUsages returned. When the value returned is not null the ResourceContentionHandler MAY return an array containing all of the ResourceUsage objects passed to it, or it MAY return a subset of those objects.

Parameters:

newRequest - The resource usage object containing the attributes of the resource request(s).

currentReservations - The set of resource usage objects that describe current resource reservations which are in conflict with the newRequest. A ResourceUsage associated with a current reservation MAY belong to an application that has been destroyed. Use of the AppID contained within such a ResourceUsage with any of the methods in org.dvb.application.AppsDatabase MAY cause a failure status to be returned.

Returns:

A prioritized array of resource usage objects. The first entry has the highest priority. This function returns null if the contention handler wants the implementation to resolve the conflict.

resourceContentionWarning

void resourceContentionWarning(ResourceUsage newRequest,
                               ResourceUsage[] currentReservations)

Warns the resource contention handler of an impending contention with a presenting ServiceContext (e.g., scheduled recording as defined by the OCAP DVR specification). If a ResourceContentionHandler is registered the implementation SHALL call this method as defined by the ResourceContentionManager.setWarningPeriod(int) method.

Parameters:

newRequest - The resource usage object containing the attributes of the resource[s] request.

currentReservations - The resource usage objects currently owned by applications which are in conflict with the newRequest. A ResourceUsage associated with a current reservation may belong to an application that has been destroyed. Use of the AppID contained within such a ResourceUsage with any of the methods in org.dvb.application.AppsDatabase MAY cause a failure status to be returned.