/**
 * A SimpleIterator only iterates over the keys, but
 * hides the data associated to the keys.
 * @author Rossmanith
 *
 * @param <K> The type of the keys.
 */
public class SimpleIterator<K> {
  /*
   * iterator is the hidden Iterator to access all the keys;
   * in essence, all calls are passed to this internal iterator.
   */
  private final Iterator<K,?> iterator;
  /**
   * Creates a new SimpleIterator from an {@link Iterator}. 
   * @param i The iterator that will provide the keys for
   *          the newly created SimpleIterator.
   */
  public SimpleIterator(Iterator<K,?> i) { iterator=i; }
  /**
   * The method is the same as in {@link Iterator#step()}.
   */
  public void step() { iterator.step(); }
  /**
   * The method is the same as in {@link Iterator#more()}.
   */
  public boolean more() { return iterator.more(); }
  /**
   * The method is the same as in {@link Iterator#key()}.
   */
  public K key() { return iterator.key(); }
}