Java in Mobile Computing

8/2/2019 Java in Mobile Computing

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Java in MobileComputing

Presented By:-

Anshul Mehrotra
http://www.sun.com/http://java.sun.com/http://java.sun.com/j2me/


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What is J2MEJ2ME is a family of specifications that definesvarious downsized versions of the standard Java2 platform; these downsized versions can beused to program consumer electronic devicesranging from cell phones to highly capablePersonal Data Assistants (PDAs), smart phones,and set-top boxes.


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Java Family


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J2ME Category

Principle: Different hardware corresponds differentJVMs, hardware which base on CDC have powerfulJVMs, and hardware which base on CIDC have KVMto support.
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two configurations J2ME

currently defines1Connected Limited Device Configuration (CLDC)

CLDC is aimed at the low end of the consumer electronicsrange. A typical CLDC platform is a cell phone or PDA witharound 512 KB of available memory. For this reason, CLDCis closely associated with wireless Java, which isconcerned with allowing cell phone users to purchase anddownload small Java applications known as MIDlets to theirhandsets. A large and growing number of cell phonevendors have signed agreements with Sun Microsystemsthat will allow them to begin using this technology, so thenumber of handsets with the capability to be programmed

in Java will probably grow rapidly in the next few years.


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two configurations J2ME

currently defines2Connected Device Configuration (CDC)

CDC addresses the needs of devices that lie

between those addressed by CLDC and the fulldesktop systems running J2SE. These devices havemore memory (typically 2 MB or more) and morecapable processors, and they can, therefore, supporta much more complete Java software environment.

CDC might be found on high-end PDAsand in smart phones, web telephones, residentialgateways, and set-top boxes.


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Profiles J2ME currently defines

Mobile Information Device Profile (MIDP)

PDA Profile (PDAP)

Foundation Profile

Personal Basis and Personal Profiles

RMI Profile

Game Profile


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The Mobile Information DeviceProfile and MIDlets

The Mobile Information Device Profile, orMIDP for short, is one such profile, intendedfor use on small footprint devices with a

limited user interface in the form of a smallscreen with some kind of input capability.

Java applications that run on MIDP devicesare known as MIDlets. A MIDlet consists of

atleast one Java class


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MIDP Hardware Requirements

Hardware Minimum Requirement

Display 96 X 54 Pixels 65,536 colors

Memory 32 KB workspace128KB MIDP Implementation8KB for MIDlets run

Input Device the device has the equivalent of a keypad thatallows the user to type the numbers 0 through

9,together with the equivalent of arrow keys and aselect button

Connectivity HTTP 1.1; TCP/IP


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MIDlet Security

No MIDlet APIs that allow access to informationalready on the device, such as address andtelephone number lists or calendars, and it is not

possible for a MIDlet to directly control thedevice.

A MIDlet can store information on a device, butthat storage is private to that MIDlet and its suite,

so the MIDlet can harm only its own data.


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How does J2ME work?

The latest Java-enabled mobile devices, you can viewa list of applications, games, and services and

choose which one interests you. The application isthen sent over the air to your handset, where it isinstalled and instantly available to use. You are nolonger limited to the small selection of games andapplications that came with your phone. And withnew content being released daily from topentertainment and software companies, you canalways find new, fun applications to download.


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Java Technology Carriers


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Java Technology Handsets


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J2ME Programming Environments

JBUILDER 7 OR 8 + BORLAND MOBILESET3.1 (Most Power Developing tools)

SUN JDK 1.4 + J2ME Wireless Toolkit

Jdk1.4+J2ME CLDC 1.04

MIDP 2.0


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Thank you

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Java in Mobile Computing

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