BinarySearchTree.java

//Squished a couple files together

package com.jeromegagner.example.trees.binary;

/**
 * Created by IntelliJ IDEA.
 * User: jgagner
 * Date: Apr 18, 2010
 * Time: 1:30:24 PM
 * To change this template use File | Settings | File Templates.
 */
public class BinaryTree {
    Node root;

    public BinaryTree(Node root){
        this.root = root;
    }

    /**
     * Finds a node  in O(log(n))
     * @param value
     * @return found node. else null
     */
    public Node findNode(int value){

        return findSubNode(this.root,value);
    }

//    recursively finds a sub node
    public Node findSubNode(Node root, int value){
        if(root == null || root.getValue() == value){
            return root;
        }else if(root.getValue() > value){
            return findSubNode(root.getLeft(),value);
        }else{
            return findSubNode(root.getRight(),value);
        }
    }

    /**
     * Utility for creating a binary tree with an array of numbers.
     * @param members members[0] will be the root node. 
     * @return
     */
    public static BinaryTree createTree(int[] members){
        Node root = new Node(null,null,members[0]);
        for(int i = 1; i < members.length; i++){
            insertNode(root, members[i]);
        }
        return new BinaryTree(root);
    }

    /**
     * @param root
     * @param value
     * @return
     */
    public static void insertNode(Node root, int value){
       if(root.getValue() >= value){
          if(root.getLeft() == null){
              root.setLeft(new Node(null,null,value));
          }else{
              insertNode(root.getLeft(),value);
          }
       }else{
          if(root.getRight() == null){
              root.setRight(new Node(null,null,value));
          }else{
              insertNode(root.getRight(),value);
          }
       }
    }
}

package com.jeromegagner.example.trees.binary;

/**
 * Created by IntelliJ IDEA.
 * User: jgagner
 * Date: Apr 18, 2010
 * Time: 1:28:09 PM
 * To change this template use File | Settings | File Templates.
 */
public class Node {
    private Node left;
    private Node right;
    private int value;

    public Node(Node left, Node right, int value) {
        this.left = left;
        this.right = right;
        this.value = value;
    }

    public Node getLeft() {
        return left;
    }

    public Node getRight() {
        return right;
    }

    public int getValue() {
        return value;
    }

    public void setLeft(Node left){
       this.left = left;
    }
    
    public void setRight(Node right){
        this.right = right;
    }
}