Sorting Tree Node and tacking nodes
<p>1) I have a tree and I will be inserting nodes into it during run time, may I know how to keep them sorted in natural order because the node will be after the last index.</p>

<p>Example: user add a product belonging to electronics, the product will appear under electronic category on everyone else "view". May How i know how to ensure the nodes under "electronics" will be sorted in natural order? </p>

<p>2) In my tree there are some objects that appear in another branch, May I know how to track those type of nodes?(2 different node but with the same data)</p>

<p>Yes I use hashmap to track normal nodes but I have problem find a solution for this issue.</p>

<p>The purpose of tracking is to update the nodes when there is an edit or update or insert into child...</p>

<p>I am thinking of using a object as the key or the hashmap so each object be individually identified.</p>
