User's Manual

80 Java™
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 up of 2 files:
- The JAD file
- The JAR file
JAD file stands for J ava™ A pplication D escriptor. It is a small file describing the
content of a JAR file.
JAR file stands for J ava™ A rchive. It refers to the application data themselves
(program, images, sound). A
JAR file can have a size of up to 200 KB.
Note: In rare circumstances, MIDlet vendors may provide no JAD file and the MIDlet
is just the JAR file. In such a case it is your sole responsibility to assess the risk of
downloading the JAR file without any possibility of consulting the JAD file.
Downloading a MIDlet (Java™ game or application)
MIDlets are easily downloaded to 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.
When you select a JAD file, your mobile phone downloads it, displays the data
contained and prompts you to acknowledge the JAR file download.
The popup displays information below:
- Name of the MIDlet, Version, Size, Name, Security status, URL.
If you do not want to download the main data (JAR file), you can refuse to
acknowledge further airtime consumption by selecting "Cancel".
If you agree on the MIDlet installation, just select OK . The MIDlet is installed with
security levels set to default values associated with its security status.
Before downloading an application, a message similar to this one may be displayed:
"Your handset cannot identify the application, please be sure of the source of the
application before installing the application".
Trademarks
Java™ and all other Java-based marks are trademarks or registered trademarks of
Sun Microsystems, Inc. in the U.S. and other countries.