public static String getDocumentNo(DocumentType docType, String strTableName, boolean updateNext) {
    if (docType == null) {
      return "";
    }
    Sequence seq = docType.getDocumentSequence();
    if (seq == null && strTableName != null) {
      OBCriteria<Sequence> obcSeq = OBDal.getInstance().createCriteria(Sequence.class);
      obcSeq.add(Restrictions.eq(Sequence.PROPERTY_NAME, "DocumentNo_" + strTableName));
      if (obcSeq != null && obcSeq.list().size() > 0) {
        seq = obcSeq.list().get(0);
      }
    }
    if (seq == null) {
      return "";
    }
    String nextDocNumber = "";
    if (seq.getPrefix() != null) {
      nextDocNumber = seq.getPrefix();
    }
    nextDocNumber += seq.getNextAssignedNumber().toString();
    if (seq.getSuffix() != null) {
      nextDocNumber += seq.getSuffix();
    }
    if (updateNext) {
      seq.setNextAssignedNumber(seq.getNextAssignedNumber() + seq.getIncrementBy());
      try {
        OBContext.setAdminMode(false);
        OBDal.getInstance().save(seq);
        OBDal.getInstance().flush();
      } finally {
        OBContext.restorePreviousMode();
      }
    }

    return nextDocNumber;
  }