Wanna learn to implement hierarchical data structure

Question

I want to learn the method of handling hierarchical data in Java
For instance if there is some kind of data which contains 6 main nodes then every node contains 2 sub nodes and there are 4 nodes under the 3rd node where as the 5th one contains two more subnodes one under another.
So how will that be implemented?
Ofcourse it must be possible to implement it but how can I do the same if I do not know the depth and number of nodes and will get it during the runtime?
I had attempted to do create some thing of this kind using Turbo C++ 3.5 but after two weeks of intensive programming I was left utterly confused with innumerable pointers and pointer to pointers and pointer to a pointer to a pointers and more. At last it was me who forgot which pointer was pointing to what.

Answer 1

Well, just start by making a Node class. To allow Nodes to have children, make each Node have an array (or arraylist, vector, etc.) of other Nodes.
for example:
class Node{
  private ArrayList<Node> children;
}Put whatever else you need in there.
You can then traverse these through methods you write, to return child nodes. If you need the Nodes to have knowledge of their parents, add a Node parent; variable in your Node class.
Essentially, keep things as simple as possible, and this will allow you to write cleaner code and also decide on the depth of the structure at runtime, like you describe.