/**
  * Check if a subkind can be removed from a procedural link.
  *
  * @param link that is being checked
  * @param subkind that is being added
  * @return <code>true</code> if the subkind can be removed from the link, <code>false</code>
  *     otherwise.
  */
 public boolean canSubkindBeRemoved(OPMProceduralLink link, String subkind) {
   return link != null && link.getSubKinds().contains(subkind);
 }
 /**
  * Check if a subkind can be added to a procedural link.
  *
  * @param link that is being checked
  * @param subkind that is being added
  * @return <code>true</code> if the subkind can be added to the link, <code>false</code>
  *     otherwise.
  */
 public boolean canSubkindBeAdded(OPMProceduralLink link, String subkind) {
   return link != null && validSubkinds.contains(subkind) && !link.getSubKinds().contains(subkind);
 }