Hello world (First java program)

Java is a high level programming language and it is used to develop the robust application. Java application program is platform independent and can be run on any operating System.

Hello world (First java program)

Java is a high level programming language
and it is used to develop the robust application. Java application program is
platform independent and can be run on any operating System. Writing Hello World
program is very simple. To write the Hello world program you need simple
text editor like note pad and jdk must be install in your machine for
compiling and running. Hello world program is the first step of java programming
language. Be careful when you write the java code in your text pad because java
is a case sensitive programming language.

For Example

hello world !=(not equal
to) Hello World

Write the following code into your note
pad to run the Hello World program .

Save the file and Please remember the location where
you save your file. In this example we have saved the file in the "C:\javatutorial\example"
directory. The file name should be match the class name and to save the file
give the .java extension. e.g. HelloWorld.java

Here is the video explanation of the program:

Compiling and Running the program

Now open the command prompt to compile the
HelloWorld.java program. Go to the directory where you have saved the file ( in
our case C:\javatutorial\example>) and issue the following command to compile
the program:

C:\javatutorial\example>javac HelloWorld.java

javac is a compiler in the java Language. Java
compiler change the programming Language into machinery language. So that the
java virtual can understand it. Once the compilation is successful a new file
will be created with the name HelloWorld.class. To run the program
issue the following command on command prompt:

C:\javatutorial\example>java HelloWorld

You will see the following result on the command
prompt.

Hello World!

Here is the screen shot of the above
steps:

In this lesson you have learned how to
write and then test the Hello World! java program.