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Java Java Objects Harnessing the Power of Objects Method Overloading

Thomas Rossini
Thomas Rossini
544 Points
Posted by Thomas Rossini
Thomas Rossini
544 Points

()) purpose?

what is the purpose of this when I see it used to create a while loop or if condition ? exa: while (dispenser.dispense())
and: if (dispenser.isEmpty())

1 Answer

Steven Parker
Steven Parker
231,184 Points
Steven Parker
Steven Parker
231,184 Points

Parentheses after a method name cause the method to be "called" (or "invoked"). Basically this just means the code in the method will run. If the method returns a value, that value will be substituted for the method call in the expression.

This is the same as with functions, it's not unique to object methods.

Thomas Rossini
Thomas Rossini
544 Points
Thomas Rossini
Thomas Rossini
544 Points

I understand that , () calls a method but I'm asking about when I see the double or triple parentheses ()) ?

Steven Parker
Steven Parker
231,184 Points
Steven Parker
Steven Parker
231,184 Points

There's two different things there. The matched parentheses () are for calling the method. The other closing one ) is part of the conditional expression that started right after the "while" or "if":

 if (dispenser.isEmpty())
//                    ()   <- this pair calls the method
//  (                   )  <- and this pair encloses the expression