/**
 * Objects that know how to compare other objects.
 *
 * @author Samuel A. Rebelsky
 * @version 1.0 of April 1999
 */
public interface Comparator {
  /**
   * Determine if two things are equal.
   */
  public boolean equals(Object alpha, Object beta);

  /**
   * Determine if one thing is less than another.
   * Pre: The two things can reasonably be compared.
   */
  public boolean lessThan(Object first, Object second);
} // interface Comparator