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What is java, What is a midlet, Downloading a midlet (java™ game or application) – Sagem myC5-2 User Manual

Page 85: Java

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Java™

What is Java™?

Java™ is a new technology enabling use of powerful applications in the mobile phone area. Business

applications and games are easily downloadable by the end-user on a Java™ featured handset.
Your mobile phone is a MIDP 2.0 compliant Java™ platform which implements WMA (SMS support) and

MMAPI (Multimedia support) options, providing an exciting environment to run highly graphical,

networked and intuitive MIDP applications.
Such applications may be, for example, a wide range of games and appealing applications like action

and logic games, agenda, e-Mail reader, Web browser…

What is a MIDlet?

A Java™ application or a game designed to run in a mobile phone is named a MIDlet (MIDP applet).
A MIDlet is usually made of 2 files:

•The JAD file

• The JAR file

JAD file stands for Java™ Application Descriptor. It is a small file describing the content of a JAR file (version, vendor name,

size…) and displayed by the mobile phone. JAD file size is usually less than 2 kilo-bytes large.
JAR file stands for Java™ Archive. It refers to the application data themselves (program, images, sound). A JAR file may be

up to 200 kilo-bytes large.
NOTE:
In rare circumstances, MIDlet vendors may provide no JAD file and the MIDlet is the JAR file alone. In such a case it is

your only responsibility to evaluate the risk to download the JAR file without possibility of consulting the JAD file.

Downloading a MIDlet (Java™ game or application)

MIDlets are easily downloaded in the mobile phone through the Games or Applications menus or through the WAP browser.
In almost all cases, you will first receive a JAD file which will be displayed on the screen.

Much care must be given in examining the content of the file as explained further.
When you select a JAD file, your mobile phone downloads it, displays data contained and prompts you to acknowledge the JAR

file download.
The popup displays information below:

• Name of the MIDlet

• Version

• Size (JAR file size)

• Vendor name

• Security status (IMPORTANT: see "Security considerations" paragraph below)

• JAR file URL.

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