Java实现二叉树

package BinaryTree;

public class main {

public static void main(String[] args) {
        Node<String> nodes = initTree();
        visit(nodes);// 遍历二叉树
        System.out.println("=======================");
        invert(nodes);
        visit(nodes);
    }

private static void invert(Node<String> node) {// 左右反转二叉树
if (node.leftTree != null || node.rightTree != null) {
            Node<String> temp = node.leftTree;
            node.leftTree = node.rightTree;
            node.rightTree = temp;
            invert(node.leftTree);// 遍历左子树
            invert(node.rightTree);// 遍历右子树
        }
    }

private static void visit(Node<String> node) {// 中序遍历
if (node != null) {
            visit(node.leftTree);// 遍历左子树
            System.out.println(node.data);// 动作
            visit(node.rightTree);// 遍历右子树
        }
    }

private static Node<String> initTree() {
        Node<String> nodes = new Node<String>("shun");// 根结点
        Node<String> node1 = new Node<String>("shun1");
        Node<String> node2 = new Node<String>("shun2");
        nodes.leftTree = node1;// 添加子节点到根结点
        nodes.rightTree = node2;
        node1.leftTree = new Node<String>("shun11");// 给node1添加子节点
        node1.rightTree = new Node<String>("shun12");
        node2.leftTree = new Node<String>("shun21");
        node2.rightTree = new Node<String>("shun22");
return nodes;
    }

}



// 节点类
package BinaryTree;

public class Node<T> {// T（type）表示泛型
public T data;
public Node<T> leftTree;
public Node<T> rightTree;

    Node(T data){
this.data = data;
this.leftTree = null;
this.rightTree = null;
    }
}