public class DailyNotes implements Cloneable, Comparable, Serializable {
  protected Date day;
  protected String notes;

  ...

  /* Interface methods */

  public int compareTo(Object o) throws ClassCastException {
    if (o instanceof DailyNotes) {
      int res= this.day.compareTo( ((DailyNotes)o).getDay() );
      if (res == 0) {
        return( this.notes.compareTo( ((DailyNotes)o).getNotes()) );
      }
      else {
        return(res);
      }
    }
    else {
      throw new ClassCastException("Error: Could not compare an object of Class "
       + o.getClass().getName() + " to a DailyNotes object");
    }
  }
  
  /* Overridden methods */

  public boolean equals(Object o) {
    if (o instanceof DailyNotes) {
      return( this.compareTo((DailyNotes)o) == 0 );
    }
    else {
      return(false);
    }
  }

  public int hashCode() {
    return( this.day.hashCode() );
  }

  public String toString() {
    return( DateFormat.getDateInstance(DateFormat.MEDIUM).format(day) );
  }

  ...

}