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Mahmoud Amin
Courses Plus Student 6,269 PointsWhy check equality
In this code
public int compareTo(Object obj){
/* I understand that here we cast the object obj to the class Treet then we assign the other variable to equal obj */
Treet other = (Treet) obj;
/* Why do we check equality between obj and other if we already assigned them to be equal at the previous step.*/
if(equals(other)) { return 0; } }
2 Answers
Kourosh Raeen
23,733 PointsYou're not checking equality between other and obj. You're checking equality between the object that invoked the equals method and other. The line:
if(equals(other))
is really this line:
if(this.equals(other))
where this refers to the current object, the one that equals() was called upon.
Mahmoud Amin
Courses Plus Student 6,269 PointsThank you so mch I really didn't know about (this) keyword
Kourosh Raeen
23,733 PointsGlad I could help! Happy coding!