J2ME:-Java 2 Micro Edition

1. An Over view of
J2ME
By Geetu Khanna

2. Using J2ME with
Wireless
Devices

3. What is J2ME?
Java2 Micro Edition
Java Platform, Micro Edition, or J2ME, is a Java platform designed for
embedded systems (mobile devices are one kind of such systems).
Devices such as:
 Mobile Phones
 Pagers
 PDA’s
 Car Navigation Systems
 Internet Appliances
 Set-Top Boxes

4. The J2ME Universe
PDAP Personal Profile
MIDP
Personal
Mobile Information Personal Basis Profile
Digitial Assistant
Device Profile
Profile
Foundation Profile
CLDC CDC
Connected, Limited Device Configuration Connected Device Configuration
J2ME
Java 2, Micro Edition

5. J2ME Profiles
The Connected Limited Device
Configuration (CLDC)
Contains a strict subset of the Java-class libraries, and is the
minimum amount needed for a Java virtual machine to operate.
CLDC is basically used for classifying innumerable devices into a
fixed configuration.
 Mobile Information Device Profile (MIDP) - Designed for mobile phones
 Information Module Profile (IMP) - is a profile for embedded, "headless"
devices such as vending machines, industrial embedded applications, security
systems, and similar devices with either simple or no display and with some
limited network connectivity.

6. J2ME Profiles
Connected Device Configuration (CDC)
The Connected Device Configuration is a subset of Java SE,
containing almost all the libraries that are not GUI related. It is richer
than CLDC.
 Foundation Profile - This profile is intended to be used by devices requiring a
complete implementation of the Java virtual machine up to and including the
entire Java Platform, Standard Edition API.
 Personal Basis Profile - The Personal Basis Profile extends the Foundation
Profile to include lightweight GUI support in the form of an AWT subset.

7. MIDP
Mobile Information
Device
Profile
Java ME devices implement a profile. The most
common of these are the Mobile Information
Device Profile aimed at mobile devices, such as
cell phones, and the Personal Profile aimed at
consumer products and embedded devices
like set-top boxes and PDAs.

8. MIDP vs J2SE
 No Native Methods
 Threading, but no use of interrupt()
 No file-based I/O
 Many classes with fewer methods
 Collections (Vector, Hashtable & Stack)

9. MIDP API
(familiar packages)
 java.io
 java.lang
 java.lang.ref
 java.util

10. MIDP API
(no so familiar
packages)
 javax.microedition.io
 javax.microedition.lcdui
 javax.microedition.lcdui.game
 javax.microedition.media
 javax.microedition.media.control
 javax.microedition.midlet
 javax.microedition.pki
 javax.microedition.rms

11. What makes up a MIDP
Application
MIDP Applications are composed of two
principle parts
JAR File – Contains all of the classes and
resources used by the application
JAD File – Application descriptor,
describes how to run the MIDP application

12. JAD Files
 Very simple NON-XML config file
 Application Name
 MIDI version
 Copyright and version information
 Location of the JAR file

13. Example JAD File
MIDlet-1: Jargoneer, Jargoneer.png, Jargoneer
MIDlet-Jar-Size: 2369
MIDlet-Jar-URL:http://www.jeffheaton.com/Jargoneer.jar
MIDlet-Name: Jargoneer
MIDlet-Vendor: Unknown
MIDlet-Version: 1.0
MicroEdition-Configuration: CLDC-1.0
MicroEdition-Profile: MIDP-1.0

14. Getting Started
What do I need?
 J2SE (http://sun.java.com)
 Sun’s J2ME Wireless Toolkit
(http://java.sun.com/products/j2mewtoolkit/)
 Internet Connection
 Publicly accessible website or public static
IP address

15. References
 Sun Microsystems J2ME
http://java.sun.com/j2me/
 Deploy your J2ME Application
http://www.devx.com/Java/Article/10688/0/pag
e/2

16. Thank You !!!