Java TV is a
Java
Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's mo ...
-based
software framework
In computer programming, a software framework is an abstraction in which software, providing generic functionality, can be selectively changed by additional user-written code, thus providing application-specific software. It provides a standard ...
designed for use on TV
set-top box
A set-top box (STB), also colloquially known as a cable box and historically television decoder, is an information appliance device that generally contains a TV-tuner input and displays output to a television set and an external source of si ...
es, based on components called
Xlets. It is currently used only on the
Connected Device Configuration, specifically for
iTV applications development.
The API includes the Xlet classes in the package javax.tv.xlet. Other packages of the public API include
# javax.tv.graphics - provides a simple rendering canvas
# javax.tv.locator - provides a locator in the style of a
URL for services and media, such as service:/SERV1
# javax.tv.service - defines a mechanism for service information (SI) databases and APIs representing the SI elements, such as the TV channels and media available for playback.
Criticisms
While the framework is general, Sun currently provides support only on
Java ME
Java Platform, Micro Edition or Java ME is a computing platform for development and deployment of portable code for embedded and mobile devices (micro-controllers, sensors, gateways, mobile phones, personal digital assistants, TV set-top ...
. For some subjects, such as media locators, it is in effect superseded by other locator standards on platforms such as
BD-J
BD-J, or Blu-ray Disc Java, is a specification supporting Java ME (specifically the Personal Basis Profile of the Connected Device Configuration or CDC) Xlets for advanced content on Blu-ray Disc and the Packaged Media profile of Globally Execu ...
.
A point of confusion is that in platforms supported as of 2008, examples such as the SvcDispXlet example from the introduction to the API, written circa 2001, are not deployable because it uses
AWT widgets such a
java.awt.Button Most iTV platforms, along with BD-J, implement Personal Basis Profile with no AWT widgets, as opposed to Personal Profile which includes the widgets.
Sun's reference implementation for Java TV attempts to limit its exposure to support issues to the full
Java Media Framework
The Java Media Framework (JMF) is a Java library that enables audio, video and other time-based media to be added to Java applications and applets. This optional package, which can capture, play, stream, and transcode multiple media formats, exten ...
by having its own small version of JMF that is internally referred to as "jmflite". As with the limitations of the
MIDP
Mobile Information Device Profile (MIDP) is a specification published for the use of Java on embedded devices such as mobile phones and PDAs. MIDP is part of the Java Platform, Micro Edition (Java ME) framework and sits on top of Connected Limi ...
emulators that Sun provides, the Java TV reference implementation provided by Sun has not been updated to make provisions for later JDK's such as removing calls to Thread.stop(). The Thread.stop() method was made a "final" method in Java 1.5 (meaning that classes which extend Thread and override stop() will fail at runtime under JRE 1.5 when the class is loaded). This implies that Sun has not yet committed to public plans or a roadmap for taking Java ME beyond JRE 1.3. If such an upgrade were to take place, it would require significant work on the part of all vendors of Java ME-enabled devices.
Why Are Thread.stop, Thread.suspend, Thread.resume and Runtime.runFinalizersOnExit Deprecated?
/ref>
See also
* Xlet
External links
Java ME Technology - Java TV API
- includes Sun's Reference Implementation
Java TV API 1.1 (JSR-927) online Javadocs
The JavaTV tutorial
References
{{Java (Sun)
Interactive television
Java (programming language)
Java device platform
Set-top box