二叉树遍历的递归实现

import java.util.ArrayDeque;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Stack;

public class BinaryTreeNode {
    int data;
    BinaryTreeNode left;
    BinaryTreeNode right;
    public BinaryTreeNode(int data,BinaryTreeNode left,BinaryTreeNode right){
        this.data = data;
        this.left = left;
        this.right = right;
    }
    public BinaryTreeNode(){

    }

    /**
     * 先序遍历二叉树
     * @param treeDate
     * @return
     */
    public BinaryTreeNode createTree(LinkedList<Integer> treeDate){
        int root = treeDate.removeFirst();
        BinaryTreeNode node = null;
        if (root != -1){
           node = new BinaryTreeNode(root,null,null);
            node.left = createTree(treeDate);
            node.right = createTree(treeDate);
        }
        return node;
    }

    /**
     * 前序遍历
     * @param root
     */
    public void BinaryTreePreRecur(BinaryTreeNode root){
        if (root != null){
            System.out.print(root.data+",");
            BinaryTreePreRecur(root.left);
            BinaryTreePreRecur(root.right);
        }
    }

    public void BinaryTreeMidRecur(BinaryTreeNode root){
        if (root != null){
            BinaryTreeMidRecur(root.left);
            System.out.print(root.data+",");
            BinaryTreeMidRecur(root.right);
        }
    }

    public void BinaryTreeBackRecur(BinaryTreeNode root){
        if (root != null){
            BinaryTreeBackRecur(root.left);
            BinaryTreeBackRecur(root.right);
            System.out.print(root.data+",");
        }
    }

}