这是递归的还是不递归的？

Question

I have 2 methods in a class, both methods have the same purpose, but one is recursive, the other is not.

I want to know if the following method called nonRecursivePrintFancyTree() is recursive or not, it does not call itself back.:

PrintFancyTree() {
    String outputString= "";
    outputString += printFancyTree( 2*index, _prefix);
    outputString += printFancyTree( 2*index + 1, _prefix);
}

So I know PrintFancyTree is recursive, it calls itself back, now here is the 'non recursive' one:

nonRecursivePrintFancyTree() {
    String outputString= "";
    outputString += this.printFancyTree( 2*index, _prefix);
    outputString += this.printFancyTree( 2*index + 1, _prefix);
}

Is it non recursive or not? It calls another method from the class.

Answer 1

It's not recursive as it doesn't call itself (or other method that calls the original), the fact that it does call a recursive method doesn't make the original method recursive. This has to do with abstraction, how "printFancyTree" works doesn't matter for "nonRecursivePrintFancyTree", what matters is what "printFancyTree" DOES.

Answer 2

You printFancyTree is defined with no arguments. That is why it is calling other method.

Redefine your method with an argument and call, it will become recursive.

Answer 3

A method that calls itself is called recursive method. The method nonRecursivePrintFancyTree doesn't call itself, therefore it's not a recursive method.