Java TV: Difference between revisions

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'''Java TV''' is thea [[Java (Sun)|Java]]-based [[software framework]] useddesigned for ause on TV [[set-top box]]es, forbased whichon thecomponents [[software]] is written incalled [[Java (programming language)|JavaXlet]]s. It currently is deployedcurrently used only on the [[Connected Device Configuration]], specifically for [[Interactive_televisionInteractive television|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 - provideprovides a locator in the style of a [[URL]] for services and media, such as service:/SERV1

# javax.tv.service - definedefines a mechanism for service information (SI) databasedatabases and APIs representing the SI elements;, whichsuch amountsas tothe TV channelchannels and media available for playback.

While the framework is general, Sun currently provides support only on [[Java Platform, Micro Edition]]. The framework is quite general but for some subjects, such as locators, it is in effect superseded by other locator standards on platforms such as [[BD-J]].

<ref>[http://java.sun.com/javame/technology/javatv/ Java ME Technology - Java TV API] - includes Sun's Reference Implementation</ref><ref>[http://java.sun.com/javame/reference/apis/jsr927/ Java TV API 1.1 (JSR-927) online Javadocs]</ref><ref>[http://www.interactivetvweb.org/tutorials/javatv/ The JavaTV tutorial]</ref>

==Criticisms==

While the framework is general, Sun currently provides support only on [[Java Platform, Micro EditionME]]. The framework is quite general but forFor some subjects, such as media locators, it is in effect superseded by other locator standards on platforms such as [[BD-J]]. Another point of confusion is that in platforms supported as of 2008, examples such as the SvcDispXlet example in this [http://java.sun.com/developer/technicalArticles/javatv/apiintro/ online introduction] to Java TV circa 2001 are still not deployable because it uses AWT widgets such as java.awt.Button . Most such platforms and BD-J implement Personal Basis Profile with no AWT widgets, as opposed to Personal Profile which includes the widgets.

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 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]

==NotesReferences==

{{reflist}}

{{Java (Sun)}}

{{software-stub}}

{{tv-tech-stub}}

[[Category:Java programming language]]

[[Category:Interactive television]]

[[pt:Java TV]]

[[Category:Java (programming language)]]

[[Category:Java device platform]]

[[Category:Set-top box]]