构建与遍历二叉搜索树

java用递归的方式实现二叉搜索树，说明一点，二叉平衡 树是二叉搜索树的进化体。二叉搜索树构建时的难点在于节点的插入，插入节点的方法与查询和类似，都是用递归的方式。

/**
 * 构建的二叉搜索树,平衡二叉树是二叉搜索树的进化体
 */
class Tree{
    int value;
    Tree left;
    Tree right;

    Tree(int value){
        this.value = value;
    }

    void addNode(Tree oldtree,Tree tree){
        if(tree.value>oldtree.value){
            if(oldtree.right==null){
                oldtree.right = new Tree(tree.value);
            }else{
                oldtree = oldtree.right;
                addNode(oldtree,tree);
            }
        }else if(tree.value<oldtree.value){
            if(oldtree.left==null){
                oldtree.left = new Tree(tree.value);
            }else{
                oldtree = oldtree.left;
                addNode(oldtree,tree);
            }
        }else if(oldtree.value == tree.value){
            return;
        }
    }

    /**
     * 二叉树的中序遍历
     * @param tree
     */
    void trasvalNode(Tree tree){
        if (tree.left!=null){
            trasvalNode(tree.left);
        }
        System.out.println(tree.value);

        if(tree.right!=null){
            trasvalNode(tree.right);
        }
    }
}

public class Test2 {
    public static void main(String args[]){
        int nums[] = {40,10,2,3,5,2,65};
        Tree tree = new Tree(nums[0]);
        for(int i=1;i<nums.length;i++){
          tree.addNode(tree,new Tree(nums[i]));
        }
        tree.trasvalNode(tree);
    }
}