Chapter 3       

First Program in Java

⦁ Syntax for deceleration of class
access specifier class ClassName
{
/* Body of class is followed by curly bracket*/
}
⦁ An outer class can be followed by either public access specifier or default access specifier.
⦁ Name of class and name of source code must be same.
⦁ The main() function must follow the following prototype :
public static void main (String [] args)
{
// Body of main() function
}
⦁ Code of HelloWorld.java
class HelloWorld
{
public static void main (String [] args)
{
System.out.println("Hello World");
}

 }
Comments :-
a. Here System is a predefined class.
b. out is a static member reference variable of System class which contains address of an variable of PrintStream class.
c. println() is a member function of PrintStream class.
Output :-
Hello World
⦁ We have to write an access specifier with every member in a class.

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