code: protected String concatPredicates(List<Predicate> predicateList) {
      List<String> conditions = new ArrayList<>();
      for (Predicate predicate : predicateList) {
        conditions.add(predicate.getCondition());
      }
      return Joiner.on(" and ").skipNulls().join(conditions);
    }
docs: Concatenate all predicates with "and" clause
  
  @param predicateList list of predicate(filter) conditions
  @return predicate