javax.tv.service.Service Maven / Gradle / Ivy
/*
* @(#)Service.java 1.32 00/10/09
*
* Copyright 1998-2000 by Sun Microsystems, Inc.,
* 901 San Antonio Road, Palo Alto, California, 94303, U.S.A.
* All rights reserved.
*
* This software is the confidential and proprietary information
* of Sun Microsystems, Inc. ("Confidential Information"). You
* shall not disclose such Confidential Information and shall use
* it only in accordance with the terms of the license agreement
* you entered into with Sun.
*/
package javax.tv.service;
import javax.tv.locator.Locator;
/**
* The Service interface represents an abstract view on
* what is generally referred to as a television "service" or
* "channel". It may represent an MPEG-2 program, DVB service, an ATSC
* virtual channel, SCTE virtual channel, etc. It represents the basic
* information associated with a service, such as its name or number,
* which is guaranteed to be available on the receiver.
*
* Internal to the receiver, each service is uniquely identified by
* information that may include system type, network ID, transport stream
* ID, service number, service number, or other information. This
* identification is encapsulated by the Locator object.
*
* Note that a Service object may represent multiple
* instances of the same content delivered over different media
* (e.g., the same service may be delivered over a terrestrial and
* cable network). A ServiceDetails object represents a
* specific instance of such content which is bound to a specific
* delivery mechanism.
*
* The information available through this object, i.e., the service name,
* service number, etc., represents information that is stored in
* the receiver and is not necessarily the same as what is broadcast in any
* broadcast service information protocol. For example, a receiver
* implementation may let the end user edit this information according to
* the user's preferences.
*
* A Service object may optionally implement an interface
* that supports service numbers. Each Service object
* must provide either a service name (via the getName method)
* or a service number (via the ServiceNumber interface).
*
* @see #getName
* @see ServiceNumber
* @see javax.tv.service.navigation.ServiceDetails
* @see Optionally implemented interfaces */
public interface Service {
/**
* This method retrieves additional information about the
* Service. This information is retrieved from the
* broadcast service information.
*
* Note that if the content represented by this Service
* is delivered on multiple transport-dependent streams there may be
* multiple ServiceDetails for it. This method
* retrieves one of them based on availability or user
* preferences. If access to all possible
* ServiceDetails is required, the service
* Locator can be transformed to transport-dependent
* Locator instances and ServiceDetails
* can be retrieved for each.
*
* This method returns data asynchronously.
*
* @param requestor The SIRequestor to be notified
* when this retrieval operation completes.
*
* @return An SIRequest object identifying this
* asynchronous retrieval request.
*
* @see javax.tv.locator.Locator
*
* @see javax.tv.service.navigation.ServiceDetails */
public abstract SIRequest retrieveDetails(SIRequestor requestor);
/**
* Returns a short service name or acronym. For example, in ATSC
* systems the service name is provided by the the PSIP VCT; in DVB
* systems, this information is provided by the DVB Service
* Descriptor or the Multilingual Service Name Descriptor. The
* service name may also be user-defined.
*
* @return A string representing this service's short name. If the
* short name is unavailable, the string representation of the
* service number is returned. */
public abstract String getName();
/**
* This method indicates whether the service represented by this
* Service object is available on multiple
* transports, (e.g., the same content delivered over terrestrial and
* cable network).
*
* @return true if multiple transports carry the same
* content identified by this Service object;
* false if there is only one instance of this service.
**/
public boolean hasMultipleInstances();
/**
* Returns the type of this service, (for example, "digital
* television", "digital radio", "NVOD", etc.) These values can be
* mapped to the ATSC service type in the VCT table and the DVB
* service type in the service descriptor.
*
* @return Service type of this Service.
**/
public ServiceType getServiceType();
/**
* Reports the Locator of this Service.
* Note that if the resulting locator is transport-dependent, it
* will also correspond to a ServiceDetails object.
*
* @return A locator referencing this Service.
*
* @see javax.tv.service.navigation.ServiceDetails
**/
public Locator getLocator();
/**
* Tests two Service objects for equality. Returns
* true if and only if:
*
* obj's class is the
* same as the class of this Service, and
*
obj's Locator is equal to
* the Locator of this Service
* (as reported by
* Service.getLocator(), and
*
obj and this object encapsulate identical data.
*
*
* @param obj The object against which to test for equality.
*
* @return true if the two Service objects
* are equal; false otherwise.
*/
public boolean equals(Object obj);
/**
* Reports the hash code value of this Service. Two
* Service objects that are equal will have identical
* hash codes.
*
* @return The hash code value of this Service.
*/
public int hashCode();
}