Tuesday 9 June 2015
Getting started with Java
Developing / Writing a Program
To write a program in text editor like node pad. Take the following simple program.
{
public static void main(String args[])
{
System.out.println("Hello World!");
}
}
Here HelloWorld is the class name of the program. Choose the following directory to save the file:
C:\Program Files\Java\jdk1.6.0\bin
On Windows, the JDK is placed in the following path or directory by default:
C:\Program Files\Java\jdk1.6.0
Then save this file like "class name.java" i.e., HelloWorld.java.
Compiling the Program
Syntax: javac filename.java
First open the Command Prompt (Press windows key+R then type "cmd" and hit Enter). Then type following code:
Execute the following command to compile your source file to bytecode:
javac HelloWorld.java
Note: If you do not set the PATH variable correctly, when you use the JDK’s tools, you will receive a message like:
'java' is not recognized as an internal or external command,
operable program or batch file.
Running the Program
Syntax: java classnameFinally, to execute the program using the following command:
Output
Hello World!
