Java Implementation Two fork tree (simple version)

Personal feeling the realization of binary tree is mainly about how to construct a binary tree. The design method of constructing two-fork tree function is varied. The following program represents the node of a binary tree by defining an inner class, and then implements some basic operations of the data structure of the two-fork tree.

 PackageTree; Public classBinarytree<e> {    //Why use static internal classes? Non-static members of external classes cannot be accessed in static inner classes     Public Static classtreenode{//E data;Object data;        TreeNode left;        TreeNode right;  PublicTreeNode () {} PublicTreeNode (Object data) { This. data =data; }        //constructs a new node with the left node as its child, right node for the child         PublicTreeNode (Object data, TreeNode left, TreeNode right) { This. data =data;  This. left =Left ;  This. right =Right ; }    }        PrivateTreeNode Root;//A data field of a class that implements a two-fork tree, that is, a root node to represent a binary tree         PublicBinaryTree () { This. root =NewTreeNode (); }    //creates a binary tree with the specified root element     PublicBinaryTree (E data) { This. root =NewTreeNode (data); }        //Add a child node to a specified node     PublicTreeNode AddNode (TreeNode parent, E data,Booleanisleft) {        if(Parent = =NULL)            Throw NewRuntimeException ("The parent node is empty, cannot add child nodes"); if(Isleft && Parent.left! =NULL)            Throw NewRuntimeException ("Node has left child node, add failed"); if(!isleft && Parent.right! =NULL)            Throw NewRuntimeException ("Node already has right child node, add failed"); TreeNode NewNode=NewTreeNode (data); if(isleft) Parent.left=NewNode; ElseParent.right=NewNode; returnNewNode; }         Public Booleanempty () {returnRoot.data = =NULL;//determine if the binary tree is empty based on the root element    }         PublicTreeNode root () {if(Empty ())Throw NewRuntimeException ("Tree empty, unable to access root node"); returnRoot; }         PublicE Parent (TreeNode node) {return NULL;//When a binary tree list is stored, access to the parent node needs to traverse the entire binary tree, as this is not implemented here .    }        //Accesses the left side of the specified node, returning the data field of its left child     PublicE Leftchild (TreeNode parent) {if(Parent = =NULL)            Throw NewRuntimeException ("Empty node cannot access its left child"); returnParent.left = =NULL?NULL: (E) Parent.left.data; }     PublicE Rightchild (TreeNode parent) {if(Parent = =NULL)            Throw NewRuntimeException ("Empty node cannot access its right child"); returnParent.right = =NULL?NULL: (E) Parent.right.data; }         Public intDeep () {returnDeep (root); }    Private intDeep (TreeNode node) {if(node = =NULL)            return0; Else{            intLeftdeep =Deep (Node.left); intRightdeep =Deep (node.right); intmax = leftdeep > Rightdeep?Leftdeep:rightdeep; returnMax + 1; }    }}

Java Implementation Two fork tree (simple version)