[URGENT Test] Desperately Confused, Instance Methods Invocation?

[Kenster102.5]

I used to be really good a Instance methods, now I am starting to really get confused. I have a re-test tomorrow on the writing a code for an instance method.
I am really confused with explicit and implicit, and how implicit uses the reserved word "this.num" or "this.den". If someone can answer this dilemma before lets say 8:15 then I will be okay.

Okay here is the question

Complete the definition of the following instance method for the Fraction class

Java:

public Fraction plus (Fraction f)

The method should return a Fraction object whose value is the sum of the implicit object parameter and the explicit parameter, f. The method should leave both its implicit and explicit parameters unchanged.

Java:

import java.awt.*; public class FractionTest {   public static void main (String[]args)   {     //I don't understand how to declare my implicit method if it is to be created as this.num and this.den    Fraction f = new Fraction();         f.num = 3;     f.den = 4;     Fraction g = new Fraction();     g = this.plus(f);     System.out.println(g.num, g.den); //I am really not sure about this anymore   }   class Fraction()   {     int num;     int den;         public Fraction plus (Fraction f)     {         return(f.num + this.num, f.den + this.den);      }   } }

I really really feel incompetent if I can't understand how a method using "this." can be invoked, I am really trying hard to understand. So please someone help me.
Thank you
Ken

[DtY]

'this' is a reference to itself, so if you do someInstance.plus(), when the function runs 'this' (inside the function) will be a reference to someInstance.

Btw, your fraction addition is wrong