How to Java Program

If you are beginner in
java , want to learn and make career in the Java technology , this is best the
page for you. Here we have explained how to learn Java and become a master
of the Java technologies.
Java is a high-level Programming language that requires a lot of effort
and work to learn and master on necessary Java technology to begin your
real life projects.
We here tried to give you a example, that helps you in understanding java
technology more easier and simpler.
Basic On Java
As we Know Java is based on the concept of Object-oriented
Programming language. It is a simple, secure, robust, multithreaded, portable,
platform independent high level programming language. This feature of Java helps
us in making a program that can run independently along in small machine. The
Java Technology is completely based on Java Virtual Machine(JVM).The JVM act as
Translator that convert the byte code into machine language which is a readable
one.
Understanding Java Technology
Java is Platform independent language that you can run your compiled code on
any operating without recompiling the source code. For a Beginners, want to
start on java Program, then you need a notepad editor which is used to edit your
java source code in it. Using a Java Compiler you can translate the source code
into byte code. The Java Compiler is used to check the Syntax error in your code. Java
has a number of compiler like JDK1.5,JDK 5.0 etc.If your code contains error then, Compiler
show the error message on your command prompt. Otherwise, it convert the source
code into byte code with extension .class file. We are
already known with Java virtual machine (JVM) on which java Technology
based on. It acts as translator and interpreter between the language and the
underlying software and hardware. The JVM act as interpreter that
convert the byte code into suitable code for the respective operating system.
Java Program for Beginner
Our first application will be simple and easy. The Program "the Good Morning India"
Application is written in Java language. Write it into a Notepad Editor or copy
it in your web browser, and save in a file named as Good Morning India. java.
This program shows the output function of programming language
by displaying the message "Good Morning India!". Java compilers check
the filename and match the class name.
Let Us Start With the Basic Programming Code
A java Program begins with public class Good
Morning India. Inside the Class, we declare Static void main function(String
args[]) .To call a method that is object independent ,static method is called.
we don't need to create the object of class or class is to be instantiate, The
System.out.println is used to display the output on the Console System.
Source Code
In Text/Notepad editor, create a file name Good Morning India. java with the
following contents:
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class GoodMorningIndia
{
public static void main (String args[]) {
System.out.println("Good Morning India!");
//Displays the output String on the Command Prompt//
}
}
/**
Displays "Good Morning India!" to the standard output.
**/ (Comment)
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To Compile this Program we need Javac Compiler, Before
working on any core java applications, you need to download and install
the Sun JDK tools known as Java Development Kits.
Before Compiling on a Command Prompt We need to
set the Class Path in the Environmental Variable Property of My Computer or set
in the Command Prompt. For the sake of Convenience, We set the Class Path
in Environmental Variable Property such that we don't need to write
repeatedly the same path in command prompt for executing the application
again and again.
Set Class Path =C:\JDK1.5\bin;
Class Path variable is only the way to tell
applications, including the Java Development tools kits, where to look for user
classes.
After Setting the Class Path ,We compile the Program
code using
Javac Good Morning India. java
Since Java is a Case sensitivity in which words can be
differ in meaning based on use of different uppercase and lowercase
letters.So,be make sure the Program code should be same typed in your Command
Prompt as you have saved your program in Notepad Editor.
If the Compilation is error free, The java return you
on the Command Prompt and create a folder of Good Morning India. class file
where you have saved the program in the respective directory. Once the Program
is in this form, it is ready to run. Otherwise, Check the class file is created
or not. In case it has been not created, the Compiler show the error message on
Command Prompt and check the further error in your Syntax of programming code.
To Run this Program code
Java Good Morning
The Command Prompt display the Output
Good Morning India!

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