How to implement a tree data-structure in Java?

Question

Is there any standard Java library class to represent a tree in Java?

Specifically I need to represent the following:

• The sub-tree at any node can have

Answer 1

public class Tree {
    private List leaves = new LinkedList();
    private Tree parent = null;
    private String data;

    public Tree(String data, Tree parent) {
        this.data = data;
        this.parent = parent;
    }
}

Obviously you can add utility methods to add/remove children.