This document discusses app development for Nokia Asha devices using Java ME. It covers the Nokia App Store, Nokia platforms like Series 40, an introduction to Java ME, and the development process using JAD and JAR files. Key topics include the CLDC and MIDP configurations, the MIDlet lifecycle, and how to get started with the Nokia SDK to emulate a device environment and create a first project.

1. App Development for
Nokia Asha Devices
with Java ME
Marlon Luz - INdT
Nokia Developer Evangelist
@marlonluz

2. WHAT IS THE
CENTER OF
INdT? RESEARCH
& DEVELOPMENT
nonprofit
with focus in development of
new concepts,
products & solutions
for areas related to
mobile tecnologies and internet

3. Training Content
• Nokia App Store
• Nokia Platforms
• Introduction to Java ME Development
• High Level UI components
• Data storage
• Publishing your App

4. Nokia App Store

5. Nokia App Store, Series40 & JavaME
120k+ apps, 15m downloads/day
Brasil: 150m downloads (total), 50m in
2012, 500k per day, 56% in Series 40,
73% of purchases are JavaME apps

6. Nokia Platforms
Java apps Phones
Series 40
Silverlight, XNA

7. Mobile Platforms
http://gs.statcounter.com/#mobile_os-ww-monthly-201201-201212

8. Mobile Platforms
http://gs.statcounter.com/#mobile_os-af-monthly-201201-201212

9. Mobile Platforms
http://gs.statcounter.com/#mobile_os-as-monthly-201201-201212

10. Nokia SDK 2.0 for Java
• Emulates the device
environment
• Location, contacts, etc.
• Emulates mobile events
like battery, sms, etc.
• IDE Integration

11. Development
• IDE Installation
• Overview JavaME
• First Project

12. JavaME Overview
• Java Micro Edition (ME) is the Java for devices with
limited resources
• Java ME brings a common platform for devices like:
• Mobile phones
• Pagers
• PDAs
• Set-top boxes
• Java ME defines a set of configurations, profiles e
optional APIs;
• Java ME enables the developers to create
applications for a large number of devices;

13. Configurations
• Support a wide variety of products that fit within
the scope of J2ME;
• Defines a Java platform for a wide variety of
devices, also defines a JVM (Java Virtual
Machine) and the minimum set of class libraries
available:
• Connected Device Configuration (CDC)
• Connected Limited Device Configuration (CLDC)

14. CLDC
• 128 kilobytes of memory to run Java;
• 32 kilobytes for memory allocation in runtime;
• No user interface;
• Low power processing, battery enabled device;
• 16-32 Mhz Processor

15. Profiles
• Needed APIs to develop applications for a
specific set of devices
• MIDP
• IMP
• PBP
• ...

16. MIDP
• Mobile Information Device Profile;
• MIDP defines the following set of classes:
• Application Lifecycle Package
• User Interface Package
Mobile Information
• Persistence Package
Device Profile
Networking
Persistent
Interface
Storage
• Networking Package
MIDlet
User
APIs
• Language and Utility Packages
CLDC Core classes
CLDC or KVM

17. MIDP
• 3 versions available:
MIDP 1.0 MIDP 2.0
Memory Requirement At least 200KB At least 256KB
High/Low-Level UI
Network API
Persistent Storage API
Game API
Secure networking
Push Registry
Signed MIDlets

18. MIDlets
• Apps Java that run on MIDP devices are known
as MIDlets
• MIDlets are defined in the
javax.microedition.midlet package
• Child of the abstract class
javax.microedition.midlet.MIDlet
• Life cycle defined and managed by methods
implemented in the MIDlet;

19. MIDlets
• An application manager controls the MIDlet running
• The MIDlet behavior is controlled by a life cycle
through methods that a MIDlet has to implement
default constructor()
startApp()
Paused Active
pauseApp()
destroyApp() destroyApp()
Destroyed

20. MIDlets
• The platform can change the state from Active to
Paused at any time
startApp()
Paused Active
pauseApp()
destroyApp() destroyApp()
Destroyed

21. MIDlets
• The method destroyApp() of a MIDlet is called when
the platform needs shutdown a MIDlet
startApp()
Paused Active
pauseApp()
destroyApp() destroyApp()
Destroyed

22. MIDlets
• Let´s see how to code a MIDlet
#stopTalking
#startCoding

23. JAD and JAR
• JAD (Java Application Descriptor)
• Provides information on the content of a JAR file
• JAR (Java Archive)
• Packaging various kinds of information (classes, images,
audio, data)
• Attributes JAR/JAD

24. Development process
Development Station MyMIDlet.jad
MyMIDlet.java Download
/deploy
javac Target Devices
Download
MyMIDlet.class /deploy
MyMIDlet.jar
preverify
MyMIDlet.class jar

25. Thanks
Marlon Luz
ext-marlon.luz@nokia.com
@marlonluz