二叉树的java实现与几种遍历

package com.tree;

public class BinaryTree {
	private int data;//数据节点
	private BinaryTree left;
	private BinaryTree right;
	
	public BinaryTree(int data){
		this.data = data;
		this.left = null;
		this.right = null;
	}
	/*
	 * 创建二叉树，返回根节点
	 * @param input
	 * @return
	 */
	public static BinaryTree createTree(int[] input){
		BinaryTree root = null;
		BinaryTree temp = null;
		for(int i = 0; i < input.length;i++){
			//创建根节点
			if(root == null){
				root = temp = new BinaryTree(input[i]);
			}else{
				temp = root;
				//添加节点
				while(temp.data != input[i]){
					if(input[i] <= temp.data){
						if(temp.left != null){
							temp = temp.left;
						}else{
							temp.left = new BinaryTree(input[i]);
						}
					}else{
						if(temp.right != null){
							temp = temp.right;
						}else{
							temp.right = new BinaryTree(input[i]);
						}
					}
				}
			}
		
		}
		return root;	
	}
	/*
	 * 前序遍历
	 * @param tree
	 */
	public static void preOrder(BinaryTree tree){
		if(tree != null){
			System.out.println(tree.data);
			preOrder(tree.left);
			preOrder(tree.right);
		}
	}
	/*
	 * 中序遍历
	 * @param tree
	 */
	public static void midOrder(BinaryTree tree){
		if(tree != null){
			midOrder(tree.left);
			System.out.println(tree.data);
			midOrder(tree.right);
		}
	}
	/*
	 * 后序遍历
	 * @param tree
	 */
	public static void posOrder(BinaryTree tree){
		if(tree != null){
			posOrder(tree.left);
			posOrder(tree.right);
			System.out.println(tree.data);
		}
	}
	/*
	 * 求二叉树的深度
	 * 
	 * @param tree
	 */
	public static int length(BinaryTree tree){
		int leftLen;
		int rightLen;
		if(tree == null){
			return 0;
		}else{
			leftLen = length(tree.left);
			rightLen = length(tree.right);
			if(leftLen > rightLen){
				return leftLen+1;
			}else{
				return rightLen+1;
			}
		}
		
	}
	/*
	 * 测试main函数
	 * 
	 * @param args
	 */
	public static void main(String[] args){
		int[] input = {4,2,6,1,3,5,7,8,10};
		BinaryTree btree = createTree(input);
		System.out.println("前序遍历：");
		preOrder(btree);
		System.out.println("中序遍历：");
		midOrder(btree);
		System.out.println("后序遍历：");
		posOrder(btree);
		System.out.println("树的深度："+length(btree));
		
	}
}