The Simplest Java Application: Hello,World!

• Since Java is object-oriented, programs are organized into modules called classes, which may have data in variables and subroutines called methods.

class HelloWorld

{ public static void main (String[] args)

{ System.out.println(“Hello World!”);

}

}

Each program is enclosed in a class definition.

main() is the first method that is run.

The notation class.method or package.class.method is how to refer to a public method (with some exceptions).

Syntax is similar to C - braces for blocks, semicolon after each statement. One difference: upper and lower case matter!

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