abstract class KeyObject
{
 public abstract String getKey();

 public boolean equalKey(String key)
 {
  return getKey().equals(key);
 }

 public boolean equalKey(KeyObject kobj)
 {
  return getKey().equals(kobj.getKey());
 }

 public boolean lessThan(String key)
 {
  return getKey().compareTo(key)<0;
 }

 public boolean lessThan(KeyObject kobj)
 {
  return getKey().compareTo(kobj.getKey())<0;
 }
}