public class BinaryTree<E>{

protected Node<E> root;

protected int size = 0;

protected INodeCreator creator = null;

public BinaryTree(){

root = null;

}

final public void insertLeft(E data, Node<E> node){

if(node.left != null){

System.out.println("왼쪽 노드가 이미 차있음");

return ;

}

if(root == null){

root = node;

}

Node<E> newNode = new Node<E>(data);

node.left = newNode;

}

final public void insertRight(E data, Node<E> node){

if(node.right != null){

System.out.println("오른쪽 노드가 이미 차있음");

return ;

}

if(root == null){

root = node;

}

Node<E> newNode = new Node<E>(data);

node.right = newNode;

}

protected int getMaxLevel(Node<E> node){

if(node == null)

return 0;

return java.lang.Math.max(getMaxLevel(node.left), getMaxLevel(node.right)) + 1;

}

public void printPreOrder(){

BinaryTreePrinter.printPreOrder(root);

}

public void printInOrder(){

BinaryTreePrinter.printInOrder(root);

}

public void printPostOrder(){

BinaryTreePrinter.printPostOrder(root);

}

public void printLevelOrder(){

BinaryTreePrinter.printLevelOrder(root);

}

public void printBFS(){

BinaryTreePrinter.printBFS(root);

}

public void print(){

BinaryTreePrinter.print(root);

}

public static class Node<E>{

// Inner class 에서는 private 라도 멤버 변수 접근 가능함!

public E element;

public Node<E> parent;

public Node<E> left;

public Node<E> right;

public Node(){

this.left = null;

this.right = null;

}

public Node(E element){

this.element = element;

this.left = null;

this.right = null;

}

public Node(E element,Node<E> parent){

this.parent = parent;

this.element = element;

this.left = null;

this.right = null;

}

public void visit(){

System.out.print(element);

}

}

protected static interface INodeCreator<E extends Comparable<E>> {

public Node<E> createNewNode(E id,Node<E> parent);

}

}