code: public static String getURIFromAbbrev(final String abbreviation) {
          String[] parts = abbreviation.split(":");
          if (parts.length == 2) {
              return getNSFromPrefix(parts[0]) + parts[1];
          }
          throw new IllegalArgumentException("Undefined prefix in " + abbreviation);
      }
docs: Given an abbreviated URI, it returns a full URI
  
  @param abbreviation the abbreviation
  @return the URI