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Slide 1: JAVA 2 Micro Edition (J2ME) José María Casanova Crespo Master on Free Software

Slide 2: Agenda ● Basic Ideas ● Configurations CLDC & CDC ● Profiles MIDP 1.0, 2.0 ● Using J2ME Wireless Toolkit ● Building an example application Master on Free Software

Slide 3: Basic Ideas ● J2ME... – ... is a subset of J2SE focused on devices with low resources (low memory, restricted screen, mobiles, PDA) – ... garbage collector is not mandatory. – ... JVM adapted to devices. – ... defines configurations and profiles Master on Free Software

Slide 4: J2ME Configurations (CDC) ● Connected Devices Configuration (CDC) – JSR36 (CDC 1.0), JSR218(CDC 1.1) – Requires 32bits microprocessor and ample memory (+2Mb RAM +2.5 Mb ROM) – 3 Profiles: ● Foundation: Java SE-like API but not GUI ● Personal Basis: includes Lightweight GUI ● Personal: includes full AWT and applets support. – See devices supporting it: web Master on Free Software

Slide 5: J2ME Configurations (CLDC) ● Connected Limited Devices Configuration (CLDC) – JSR30(CLDC 1.0),JSR139(CLDC 1.1) – Requires 16bits CPU, memory 160-512Kb,limited power, connectivity to some kind of network – CLDC 1.1 includes floating points operations. – Profiles: ● MIDP: Mobile Information Device Profile. ● Information Module Profile – API is very limited, go to API documentation Master on Free Software

Slide 6: MIDP Profile ● Supported by almost any CELL phones ● Defines lower level programming interfaces ● JSR37 (MIDP 1.0), JSR118 (MIDP 2.0) ● There are several optional Packages – http://developers.sun.com/mobility/apis/ Master on Free Software

Slide 7: J2ME Wireless Toolkit ● Includes: – CLDC 1.1 – MIDP 2.0 – JTWI (Java Technology for Wireless Industry) – Wireless Messaging API (WNA) – Mobile Media API (MMA) – PDA Optional Packages for J2ME (JSR75) – Bluetooth (JSR82), web services (JSR172), 3D API (JSR184) Master on Free Software

Slide 8: PhoneME ● December 22th, 2008, JAVA ME source is licensed as GPLv2. ● Implementation of CLDC and MIDP. ● Complete or partial implementation of optional packages (JSR) ● https://phoneme.dev.java.net/ Master on Free Software

Slide 9: IDEs ● NetBeans IDE 6.0 – using Mobility version includes complete API for J2ME – includes visual mobile designer – http://www.netbeans.org ● Eclipse using Eclipse ME Plugin – connects the Wireless Toolkit to Eclipse IDE – http://eclipseme.org Master on Free Software

Slide 10: Practice ● will work with NetBeans 6.0, download and install. ● check about your cell phone Java features – http://developers.sun.com/mobility/device/pub/device/list.do ● following two tutorials – http://www.netbeans.org/kb/60/mobility/quickstart.html – http://www.netbeans.org/kb/60/mobility/smscomposer.html ● install and test samples on your cell phone. Master on Free Software