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70 Java™
When you set a more permissive authorization to a security group than the current value, mobile phone asks you to
confirm your increased risk exposure.
The maximum risk exposure increase is limited by the security status. Depending of the manufacturing configuration, it
means, for example, that "Net Access" security group authorization cannot be set to a permissive value higher that "Session"
for an "uncertified" MIDlet ("Single confirmation" and "Always" are unavailable in the security configuration menu) but an
operator "certified" MIDlet may have all permission values available without any limitations.
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 J ava™ A pplication D escriptor. 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 J ava™ A rchive. 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.
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