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Jake Goodman
3,381 Pointsequals(Object obj)
At the beginning of the method compareTo(). we check if (equals(other)). I am not clear as to what is being compared at this line. We have seen the .equals() method on Strings, where there is a string being compared to another string: For example : "banana".equals("apple") But in the example above: if (equals(other)) I have no idea what is being compared. What is being compared to other?
4 Answers
Alexander La Bianca
15,959 PointsYou are comparing the current instance of Tree to 'other'. other will be another instance of Tree that is passed into the compareTo() method. So you will essentially call it like this:
Tree tree1 = new Tree() //i don't know what goes into the constructor so i just leave it blank for demonstration only
Tree tree2 = new Tree()
tree1.compareTo(tree2); //tree2 is other in this case.
felixwin
14,939 PointsThis might be a shorthand for "this.equals(other)". Is that right, or am I missunderstanding something here?
or yochanan
1,312 PointsWhen you don't provide a prefix to equals, it assumes you mean "this.equals(..)". The "this." annotation means: the instance you're invoking the handler from.
Erol Kemikkiran
14,117 Pointsif (equals(other)) compares the object references. It checks if its in the same place in memory.
Ewerton Luna
Full Stack JavaScript Techdegree Graduate 24,031 PointsEwerton Luna
Full Stack JavaScript Techdegree Graduate 24,031 PointsI'm having the same question he had. I kinda get what you said, but a bit of doubt still remais. I didn't know you could com a method (like equals()) without calling it on an object. I've seen until now all methods being called on objects using a dot.... I'm supposing that there are cases you can just call it like Craig did.