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