1 / 27

J2ME - PowerPoint PPT Presentation

J2ME . Prepared by: Gaery- Ronny Alan- Andy. Why Technology for Mobile Devices?. The nature of wireless devices is changing Old devices: All the software hard-coded by the device manufacturer New devices: Can be customized by dynamically loading software over the air

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

Download Presentation


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


  • Prepared by:

  • Gaery- Ronny

  • Alan- Andy

Why Technology for Mobile Devices?

  • The nature of wireless devices is changing

  • Old devices:

    • All the software hard-coded by the device manufacturer

  • New devices:

    • Can be customized by dynamically loading software over the air

    • New opportunities for manufacturers, operators, and developers!

JAVA Architecture

What is J2ME ?

  • A collection of Java APIs for the development of software for resource constrained devices such as PDAs and cell phones.

  • Provides a robust, flexible environment for applications running on those devices.

Why is J2ME useful…

  • J2ME complements configurations with profiles, software to match the hardware.

    • Each configuration supports several profiles.

    • The most common profile in mobile phones is MIDP, the Mobile Information Device Protocol, which adds networking, user interface, and persistent storage support to the CLDC configuration.

    • Requirement for MIDP: screen at least 96 pixels wide and 54 pixels tall

  • J2SE re-use

    • J2ME is designed to re-use J2SE code wherever possible, or at least to pretend to.

    • Within the scope of features supported by a given configuration and set of profiles, wherever possible the J2ME implementation must not change interfaces or behavior from the J2SE original.

What kinds of problems does this technology solve well ?

  • Allow mobile devices to run full application.

  • Creates a graphical user interface for applications in the mobile devices.

J2ME Connected LimitedDevice Configuration (CLDC)

J2ME Mobile InformationDevice Profile (MIDP)

MIDlet – J2ME Software

  • MIDP applications are called MIDlets.

    • MIDlets are groups of classes, one of which is derrived from the abstract class javax.microedition.midlet.MIDlet

  • The user selects and launches the MIDlet.

    • At this point, the MIDlet enters the KVM and the lifecycle methods of the MIDlet are invoked.

J2ME – CLDC Stack

Why is it cool?

J2ME developers can develop on their PC and test the code using an emulator

Why is it cool?

  • Most applications written in Java can be virtually shown in the mobile devices.

  • Sample Codes and Applications . . .

Wireless Access Protocol

What is WAP?

  • WAP (Wireless Application Protocol) was designed to allow wireless devices, and their limited screens and connection speeds, to access Internet and intranet applications.

  • The goal was to offer a license-free standard to the entire wireless industry so that anyone would be able to develop WAP-based services.

  • WAP standardizes access not only for mobile phones but also for PDAs (personal digital assistants) and pagers.

How is it used?



  • optimized for mobile networks with narrow bandwidths.

  • Good for mobile devices with small screens and Limited keys for user entry.

  • Good for devices with little memory storage and limited processing and battery power.

  • Faster loading time.

  • User interface is very minimal.

  • Low security.

  • Requires constant airtime for stand-alone or offline operations.


For Mobile Environment

Ajax for mobile web environment

  • Shorthand for Asynchronous JavaScipt and XML

  • The Ajax technique uses a combination of:

  • XHTML, HTML, and CCS stylesheet.

  • Document Object model , JavaScript.

  • XMLHttpRequest

  • XML

Ajax Web Application Model

.Net Mobile

Major competitor of J2ME

What is .Net Mobile

  • .NET Mobile is a set of server-side Web Forms and Controls for building applications for wireless mobile devices, like web phones and PDAs.

  • .NET Mobile is an extension to Microsoft ASP.NET and the Microsoft's .NET Framework.

Why .Net Mobile?

  • Different mobile devices support different programming languages. Some support WAP and WML, some support HTML or a limited version of HTML, and some support both or a different language.

  • To support all types of mobile devices, developers must create one different application for each language.

Why .Net Mobile?

  • Support for Multiple Markup Languages

    • Cell phones and other devices that use Wireless Application Protocol (WAP) to display Wireless Markup Language (WML)

    • Devices such as Pocket PCs, which display Hypertext Markup Language (HTML) content

  • Write Once, Access from Multiple Devices

How does it work?

  • A web client requests a web page

  • The request travels the Internet

  • The request is received by IIS

  • The request is handled by the .NET framework

  • .NET Mobile handles any mobile device requirements

  • The page is returned to the client

What set J2ME apart from the other?

  • J2ME is the most popular web technology that is used by today’s mobile devices.

  • Allows mobile devices to run applications written in JAVA.

  • Little difference if compared with .NET mobile because .NET is also an Integrated Development Environment.


  • Login