First Program

The "Hello World!" Application

The following sections provide detailed instructions for compiling and running a simple "Hello World!" application. The first section provide how to create Java Application in simple word process program. Finally provide details how to make application for NetBeans IDE. Because NetBeans IDE has some Advanced features.

01. "Hello World" for Microsoft Windows.

It's time to write your first application! The following instructions are for users of Windows XP Professional, Windows XP Home, Windows Server 2003, Windows 2000 Professional, and Windows Vista. Instructions for Solaris OS and Linux are in the "Hello World!" for Solaris OS and Linux section.

A Checklist

To write your first program, you'll need:

1.	The Java SE Development Kit 6 (JDK 6) You can download the Windows new version now.* (Make sure you download the JDK, not the JRE.) Consult the installation instructions.** * http://java.sun.com/javase/6/download.jsp **http://java.sun.com/javase/6/webnotes/install/
2.	A text editor In this example, we'll use Notepad, a simple editor included with the Windows platforms. You can easily adapt these instructions if you use a different text editor.

These two items are all you'll need to write your first application.

Introducing about Java and Compiling are Following things............(Still Data Adding)

Tutorials - Getting Started

The Java Technology Phenomenon.

Talk about Java technology seems to be everywhere, but what exactly is it? The following sections explain how Java technology is both a programming language and a platform, and provide an overview of what this technology can do for you.

About the Java Technology.

Java technology is both a programming language and a platform.

The Java Programming Language.

The Java programming language is a high-level language that can be characterized by all of the following buzzwords:

• Simple

• Architecture neutral

• Object oriented

• Portable

• Distributed

• High performance

• Multithreaded

• Robust

• Dynamic

• Secure

Each of the preceding buzzwords is explained in The Java Language Environment, a white paper written by James Gosling and Henry McGilton.

White Paper can Download....

In the Java programming language, all source code is first written in plain text files ending with the .java extension. Those source files are then compiled into .class files by the javac compiler. A .class file does not contain code that is native to your processor; it instead contains bytecodesthe machine language of the Java Virtual Machine (Java VM). The java launcher tool then runs your application with an instance of the Java Virtual Machine

Compiling and Running an Application

Because the Java VM is available on many different operating systems, the same .class files are capable of running on Microsoft Windows, the Solaris Operating System (Solaris OS), Linux, or Mac OS. Some virtual machines, such as the Java HotSpot virtual machine,perform additional steps at runtime to give your application a performance boost. This includes various tasks such as finding performance bottlenecks and recompiling (to native code) frequently used sections of code

White Paper can Download....

Through the Java VM, The same the application is capable of running on multiple platform.

The Java Platform.

A platform is the hardware or software environment in which a program runs. We've already mentioned some of the most popular platforms like Microsoft Windows, Linux, Solaris OS, and Mac OS. Most platforms can be described as a combination of the operating system and underlying hardware. The Java platform differs from most other platforms in that it's a software-only platform that runs on top of other hardware-based platforms.

The Java platform has two components:

• The Java Virtual Machine

• The Java Application Programming Interface (API)

You've already been introduced to the Java Virtual Machine; it's the base for the Java platform and is ported onto various hardware-based platforms.

The API and Java Virtual Machine insulate the program from the underlying hardware.

The API is a large collection of ready-made software components that provide many useful capabilities. It is grouped into libraries of related classes and interfaces; these libraries are known as packages. The next section highlights some of the functionality provided by the API.

As a platform-independent environment, the Java platform can be a bit slower than native code. However, advances in compiler and virtual machine technologies are bringing performance close to that of native code without threatening portability.

History of Java

James Gosling initiate Java Language in June 1991 for use in one of his many Set - Top Box Project. The language, initially called Oak after an Oak Tree that stood outside Gosling's office, also went by the name Green and ended up later renamed as Java, from a list of random a list of random words. Gosling aimed to implement a virtual machine and a language that had a familiar C/C++ style of notation.

Sun Microsystems released the first public implementation as Java 1.0 in 1995. It promised "Write once, Run Anywhere"(WORA), providing no-cost run-times on popular Platforms. Fairly secure and featuring configurable security, it allowed network-and file-access restrictions. Major Web browsers soon incorporated the ability to run Java applets within web pages, and Java quickly became popular.

With the advent of Java 2 (Released initially as J2SE 1.2 in December 1998), new version had multiple configuration built for different types of platforms. For example, J2EE targeted enterprises application and the greatly stripped down version J2ME for mobile applications. J2SE designed the Standard Edition. In 2006, for marketing purpose, Sun renamed new J2 version as Java EE, Java ME, and Java SE, respectively.

What can Java Technology Do ?

The general-purpose, high-level Java programming language is a powerful software platform. Every full implementation of the Java platform gives you the following features:

Development Tools The development tools provide everything you'll need for compiling, running, monitoring, debugging, and documenting your applications. As a new developer, the main tools you'll be using are the javac compiler, the java launcher, and the javadoc documentation tool.

Application Programming Interface (API) The API provides the core functionality of the Java programming language. It offers a wide array of useful classes ready for use in your own applications. The core API is very large; to get an overview of what it contains, consult the Java SE Development Kit 6 (JDK 6) documentation.

Deployment Technologies The JDK software provides standard mechanisms such as the Java Web Start software and Java Plug-In software for deploying your applications to end users. User Interface Toolkits The Swing and Java 2D toolkits make it possible to create sophisticated Graphical User Interfaces (GUIs). Integration Libraries Integration libraries such as the Java IDL API, JDBC API, Java Naming and Directory Interface ("J.N.D.I.") API, Java RMI, and Java Remote Method Invocation over Internet Inter-ORB Protocol Technology (Java RMI-IIOP Technology) enable database access and manipulation of remote objects.

How Will Java Technology Change My Life ?

We can't promise you fame, fortune, or even a job if you learn the Java programming language. Still, it is likely to make your programs better and requires less effort than other languages. We believe that Java technology will help you do the following:

Get started quickly Although the Java programming language is a powerful object-oriented language, it's easy to learn, especially for programmers already familiar with C or C++.

Write less code Comparisons of program metrics (class counts, method counts, and so on) suggest that a program written in the Java programming language can be four times smaller than the same program written in C++.

Write better code The Java programming language encourages good coding practices, and automatic garbage collection helps you avoid memory leaks. Its object orientation, its JavaBeans component architecture, and its wide-ranging, easily extendible API let you reuse existing, tested code and introduce fewer bugs.

Develop programs more quickly The Java programming language is simpler than C++, and as such, your development time could be up to twice as fast when writing in it. Your programs will also require fewer lines of code.

Avoid platform dependencies You can keep your program portable by avoiding the use of libraries written in other languages.

Write once, run anywhere Because applications written in the Java programming language are compiled into machine-independent bytecodes, they run consistently on any Java platform.

Distribute software more easily With Java Web Start software, users will be able to launch your applications with a single click of the mouse. An automatic version check at startup ensures that users are always up to date with the latest version of your software. If an update is available, the Java Web Start software will automatically update their installation.