InvokeDemo.java

Download InvokeDemo source file

// Demonstration of various ways to invoke a method in Java.
// Written 2002 by Wayne Pollock, Tampa Florida USA.

class InvokeDemo
{
    public static void main ( String [] args )
    {
        InvokeDemo obj = new InvokeDemo();

        int i;
        i = obj.add( 2, 3 );
//      i = InvokeDemo.add( 2, 3 );  // Only if "add" declared "static".
//      i = add( 2, 3 );  // Only if "add" is "static" in current class.

        obj.aMethod();
    }

    /* static */ int add ( int num1, int num2 )
    {
        return num1 + num2;
    }

    void aMethod ()    // A non-static method.  Such methods have a 
                       // "current" object.
    {
        InvokeDemo obj = new InvokeDemo();

        int answer;
        answer = obj.add( 2, 3 );
//      answer = InvokeDemo.add( 2, 3 );  // Only if "add" is "static".
        answer = add( 2, 3 );  // Only if add is method of curent class.

        System.out.println( answer );
    }
}