Java TV: Difference between revisions

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'''Java TV''' is thea term[[Java used(Sun)|Java]]-based [[software framework]] designed for ause on TV [[set-top box]]es, forbased whichon thecomponents called [[softwareXlet]]s. It is writtencurrently used only inon the [[objectConnected orientedDevice Configuration]], [[programmingspecifically language]]for [[JavaInteractive (programming language)television|JavaiTV]] applications development.

The API includes the Xlet classes in the package javax.tv.xlet. Other packages of the public API include

Java version 2 has 3 variants:

# javax.tv.graphics - provides a simple rendering canvas

* J2SE: the "Standard Edition"

# javax.tv.locator - provides a locator in the style of a [[URL]] for services and media, such as service:/SERV1

* J2EE: the "Enterprise Edition", that extends J2SE with standards for backend programming

# 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.

* J2ME: the "Micro Edition", that requires much less of devices it runs on with respect to peripherals, e.g., where the user interface or network is concerned. Java set-top boxes are based on J2ME.

==Criticisms==

While the framework is general, Sun currently provides support only on [[Java ME]]. For some subjects, such as media locators, it is in effect superseded by other locator standards on platforms such as [[BD-J]].

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 [[Abstract Window Toolkit|AWT]] widgets such as [http://java.sun.com/javase/6/docs/api/java/awt/Button.html 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.<ref>[http://java.sun.com/developer/technicalArticles/javatv/apiintro/ Introduction to Digital TV Applications Programming] By Monica Pawlan, February 2001</ref>

Sun's reference implementation for Java TV attempts to limit its exposure to support issues to the full [[Java Media Framework]] by having its own small version of JMF that is internally referred to as "jmflite". As with the limitations of the [[MIDP]] 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.<ref>[http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Thread.html#stop() JRE 1.5 Thread.stop() javadoc]</ref><ref>[http://java.sun.com/j2se/1.5.0/docs/guide/misc/threadPrimitiveDeprecation.html Why Are Thread.stop, Thread.suspend, Thread.resume and Runtime.runFinalizersOnExit Deprecated?]</ref>

==See also==

{{Portal|Computer programming}}

*[[Xlet]]

==External links==

* [http://java.sun.com/javame/technology/javatv/ Java ME Technology - Java TV API] - Includes includes Sun's Reference Implementation

* [http://java.sun.com/javame/reference/apis/jsr927/ Java TV API 1.1 (JSR-927) online Javadocs]

* [http://www.mhp-interactive.org/tutorials/javatv/ The JavaTV tutorial]

==References==

{{reflist}}

{{Java (Sun)}}

{{tv-tech-stub}}

[[Category:JavaInteractive programming languagetelevision]]

[[Category:Java (programming language)]]

[[Category:Java device platform]]

[[Category:Set-top box]]