Simple tree structure

Node.java

import java.util.ArrayList;
import java.util.List;

public class Node<T> {
	private Node<T> parent;
	private List<Node<T>> children;
	private T data;

	public Node(Node<T> parent) {
		this(parent, null);
	}

	public Node(Node<T> parent, T data) {
		this.parent = parent;
		this.children = new ArrayList<Node<T>>();
		if (this.parent != null)
			this.parent.getChildren().add(this);
		this.data = data;
	}

	public boolean hasParent() {
		return parent != null;
	}

	public Node<T> getParent() {
		return parent;
	}

	public T getData() {
		return data;
	}

	public void setData(T data) {
		this.data = data;
	}

	public boolean hasChildren() {
		return children.size() != 0;
	}

	public List<Node<T>> getChildren() {
		return children;
	}
}

Tree.java

public class Tree<T> {
	private Node<T> root;
	
	public Tree(T name) {
		this.root = new Node<T>(null, name);
	}
	public Node<T> getRoot() {
		return root;
	}
	public int size() {
		return count(root);
	}
	private int count(Node<T> node) {
		int count = 1;
		for (Node<T> child : node.getChildren())
			count += count(child);
		return count;
	}
	private String toString(Node<T> node, int level) {
		StringBuilder builder = new StringBuilder();
		for (int i = 0; i < level; i++) {
			builder.append("-");
		}
		builder.append(node.getData() + System.lineSeperator());
		for (Node<T> child : node.getChildren()) {
			builder.append(toString(child, level + 1));
		}
		return builder.toString();
	}
	@Override
	public String toString() {
		return toString(root, 0);
	}
}