Friday, August 21, 2009

Casting of Computers

if you are a IT related person or interested to know how the machine you are currently working was this post. It is about how the cast of a computer occured during the past decades within various obstacles and goals.

First Generation - 1940-1956: Vacuum Tubes

First generation computers relied on machine language, the lowest-level programming language understood by computers, to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts.

Second Generation - 1956-1963: Transistors

Second-generation computers moved from cryptic binary machine language to symbolic, or assembly, languages, which allowed programmers to specify instructions in words. High-level programming languages were also being developed at this time, such as early versions of COBOL and FORTRAN. These were also the first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology.

Third Generation - 1964-1971: Integrated Circuits

Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors.

Fourth Generation - 1971-Present: Microprocessors

The microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. The Intel 4004 chip, developed in 1971, located all the components of the computer - from the central processing unit and memory to input/output controls - on a single chip.

As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices.

Fifth Generation - Present and Beyond: Artificial Intelligence

Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. The use of parallel processing and superconductors is helping to make artificial intelligence a reality. Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.

Human cast

Human means an animal. But a kind of special animal among other animals. How this Human has become so special among others. This is a matter to be discussed deeply. If you are a human, you might think why you are reading this or rather standing in front of your computer like this without fighting with other animals to survive. You also might be between the animals if your early man kind did not have any feelings for new inventions or rather a compassion for standing upon with each other. Some how They have achieved their goals and so you have been able to spend a much more comfortable life in comparison with your own neighbours(animals) in early ages.

Some says that inventing of the tyre is the key point. But some says inventing the flame made human to cast so rapidly among the other kind of species. Capability of grabing a thing from fingers made human casting so fast is some one else's idea.
Human can use their brain up to twenty present is another concept. Feeling things like love, compassion, anger more sensitively than the other species is another intention. One can argue on these for days. But no one can tell exactly which is the most closer reason to be like this.

What ever the reason may be, one thing can be expressed for sure that this rapid development of humans has become the greatest destruction of not only the human kind but hole earth also. So This human should be responsible for the lost of every animals of this planet day by day.

We have developed. But we are not civilised.

Thursday, August 20, 2009

Introduction to J2ME

Hi everyone,

Today Everybody in Information Technology Industry, use to follow java as a programming language. But the problem is among majority of them stop learning further more after completing J2SE or j2EE. But today in most IT companies expect wireless technology from developers as now the technology has gone beyond the Global village concept and wireless mobility has become a one of the key factor to that.
When talking about wireless mobility, learning java micro edition can not be neglected. So this post will give you a little introduction on J2ME and its basic features.


This tutorial assumes that you have some familiarity with general programming concepts and the Java language.

What is J2ME?

J2ME stands for Java 2, Micro Edition. It is a stripped-down version of Java targeted at devices which have limited processing power and storage capabilities and intermittent or fairly low-bandwidth network connections. These include mobile phones, pagers,wireless devices and set-top boxes among others.

A Sample Wireless Stack would consist of:

  • Profiles
  • Configurations
  • Java Virtual Machines
  • Host Operating System

What is a J2ME Configuration?

A configuration defines the minimum Java technology that an application developer can expect on a broad range of implementing devices.

J2ME Connected, Limited Device Configuration (CLDC)

  • specifies the Java environment for mobile phone, pager and wireless devices
  • CLDC devices are usually wireless
  • 160 - 512k of memory available for Java
  • typically has limited power or battery operated
  • network connectivity, often wireless, intermittent, low-bandwidth (9600bps or less)

J2ME Connected Device Configuration (CDC)

  • describes the Java environment for digital television set-top boxes, high end wireless devices and automotive telematics systems.
  • device is powered by a 32-bit processor
  • 2MB or more of total memory available for Java
  • network connectivity, often wireless, intermittent, low-bandwidth (9600bps or less)

These two configurations differ only in their respective memory and display capabilities.

What is a J2ME Profile?

A specification layer above the configuration which describes the Java configuration for a specific vertical market or device type.

J2ME Profiles

J2ME Mobile Information Device Profile (MIDP)

  • this is the application environment for wireless devices based on the CLDC
  • contains classes for user interface, storage and networking

J2ME Foundation Profile, Personal Basis, Personal and RMI profiles

  • these are profiles for devices based on the CDC, which are not addressed in this tutorial

Virtual Machines

The CLDC and the CDC each require their own virtual machine because of their different memory and display capabilities. The CLDC virtual machine is far smaller than that required by the CDC and supports less features. The virtual machine for the CLDC is called the Kilo Virtual Machine (KVM) and the virtual machine for the CDC is called the CVM.

In my next post I will show how to create a simple J2ME application using netbeans IDE.

Thank you.