A simple Java program, its compilation and execution

Program

     class Welcome { 

           // A java program will start from here. 

           public static void main(String args[]) { 

                    System.out.println(" Welcome to Java-Samples!!! "); 

           } 

       }

Compilation 

After we have written our program we need to compile and run the program. For that we need to use the compiler called javac which is provided by java. Go to the command prompt and type the file name as shown here. 

                                                       c:\>javac Welcome.java

The javac compiler will create a class file called Welcome.class that contains only bytecodes. These bytecodes have to be interpreted by a Java Virtual Machine(JVM) that will convert the bytecodes into machine codes.

Execution 

Once we successfully compiled the program, we need to run the program in order to get the output. So this can be done by the java interpreter called java. In the command line type as shown here.

                                                         c:\>java Welcome 

So the output will be displayed as
                                                   Welcome to Java-Samples!!!