TreeBFS

import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.Queue;

public class MyTreeBFS {

    public static void main(String[] args) {
        Node<String> root = createTree();
        System.out.print("First Search: ");

        levelOrderQueue(root);

    }

    private static Node<String> createTree() {
        Node<String> root = new Node<>("Пенка и Велислав -->");

        Node<String> father = new Node<String>("Валентин -->");
        root.left = father;

        Node<String> sister = new Node<String>("Олимпия -->");
        root.left.left = sister;

        Node<String> me = new Node<String>("Валентина");
        root.left.right = me;


        return root;
    }

    public static void levelOrderQueue(Node root) {
        Queue<Node> q = new LinkedList<Node>();
        if (root == null)
            return;
        q.add(root);
        while (!q.isEmpty()) {
            Node n = q.remove();
            System.out.print(n.data + " ");
            if (n.left != null)
                q.add(n.left);
            if (n.right != null)
                q.add(n.right);

        }
    }

    static class Node<T> {

        private T data = null;

        private List<Node<T>> children = new ArrayList<>();
        Node<T> left;
        Node<T> right;

        public Node(T data) {
            this.data = data;
            this.left = null;
            this.right = null;
        }

        public T getData() {
            return data;
        }

    }
}