Java Platform, Micro Edition (Java ME) Interview Questions And Answers - DoAnswers.com

Java ME Platform represents the only truly open solution for building mobile applications for the industry. The technology allows portability of applications between platforms and investments are kept to a minimum through the possibility of reuse. The continuous platform evolution is driven by the increasing demands for capabilities and performance in the industry and assured through the definition of the platform components and APIs in the Java Community Process. The fact that the technology is open for anyone to use the community of developers creating applications for the platform is large and increasing. This assures the continuous improvement and availability of applications for the platform which in turn drives business for everybody involved in the eco-system. On top of this the platform itself represents a high performance and secure platform for mobile applications. The Java ME technology ecosystem evolves around a number of different players in the industry, all of them participating in , and influencing, the continuous improvement of the technology and platform. The end users are constantly demanding new features and capabilities to their services. The content developers adopts the user requirements and creates new appealing services with new capabilities. The OEMs creates new capable devices to host the new services and features and also creates new demands by presenting new capabilities to the end users. Carriers creates the mobile environment to host and deploy services on and also drives the exploration of new business-driving services to the end users. This constant evolution of demands and capabilities is the single most important reason for the success of the Java platform and ensures it will continue to evolve into the future needs of everyone involved in the eco-system.

The KVM is a compact Java virtual machine (JVM) that is designed for small devices. It supports a subset of the features of the JVM. For example, the KVM does not support floating-point operations and object finalization. The CLDC specifies use of the KVM. According to folklore, the 'K' in KVM stands for kilobyte, signifying that the KVM runs in kilobytes of memory as opposed to megabytes.

A Local Area Network (LAN) is a group of devices connected with various communications technologies in a small geographic area. Ethernet is the most widely-used LAN technology. Communication on a LAN can either be with Peer-to-Peer devices or Client-Server devices.

LCDUI is a shorthand way of referring to the MIDP user interface APIs, contained in the javax.microedition.lcdui package. Strictly speaking, LCDUI stands for Liquid Crystal Display User Interface. It's a user interface toolkit for small device screens which are commonly LCD screens.

The Mobile Execution Environment (MExE) is a specification created by the 3GPP which details an applicatio n environment for next generation mobile devices. MExE consists of a variety of technologies including WAP, J2ME, CLDC and MIDP.

A MIDlet is an application written for MIDP. MIDlet applications are subclasses of the javax.microedition.midlet.MIDlet class that is defined by MIDP.

MIDlets are packaged and distributed as MIDlet suites. A MIDlet suite can contain one or more MIDlets. The MIDlet suite consists of two files, an application descriptor file with a .jad extension and an archive file with a .jar file. The descriptor lists the archive file name, the names and class names for each MIDlet in the suite, and other information. The archive file contains the MIDlet classes and resource files.

The Mobile Information Device Profile (MIDP) is a specification for a J2ME profile. It is layered on top of CLDC and adds APIs for application life cycle, user interface, networking, and persistent storage.

The Next Generation MIDP specification is currently under development by the Java Community Process. Planned improvements include XML parsing and cryptographic support.

Mobitex is a packet-switched, narrowband PCS network, designed for wide-area wireless data communications. It was developed in 1984 by Eritel, an Ericsson subsidiary, a nd there are now over 30 Mobitex networks in operation worldwide.