code: public BundleLinkComponent getLink(String theRelation) {
      org.apache.commons.lang3.Validate.notBlank(theRelation, "theRelation may not be null or empty");
      for (BundleLinkComponent next : getLink()) {
        if (theRelation.equals(next.getRelation())) {
          return next;
        }
      }
      return null;
    }
docs: Returns the {@link #getLink() link} which matches a given {@link BundleLinkComponent#getRelation() relation}.
  If no link is found which matches the given relation, returns <code>null</code>. If more than one
  link is found which matches the given relation, returns the first matching BundleLinkComponent.
  
  @param theRelation
  The relation, such as "next", or "self. See the constants such as {@link IBaseBundle#LINK_SELF} and {@link IBaseBundle#LINK_NEXT}.
  @return Returns a matching BundleLinkComponent, or <code>null</code>
  @see IBaseBundle#LINK_NEXT
  @see IBaseBundle#LINK_PREV
  @see IBaseBundle#LINK_SELF