Represents a node of the Tree<T> class. The Node<T> is also a container, and
can be thought of as instrumentation to determine the location of the type T
in the Tree<T>.
Convenience ctor to create a Node<T> with an instance of T.
data an instance of T.
Return the children of Node<T>. The Tree<T> is represented by a single
root Node<T> whose children are represented by a List<Node<T>>. Each of
these Node<T> elements in the List can have children. The getChildren()
method will return the children of a Node<T>.
- the children of Node<T>
Adds a child to the list of children for this Node<T>. The addition of
the first child will create a new List<Node<T>>.
child a Node<T> object to set.