docs: public List<Condition> getAndConditions() {
  		if (null == subConditions) {
  			return null;
  		}
  		List<Condition> ret = new ArrayList<Condition>();
  		for (Condition subContion : subConditions) {
  			if (AND.equals(subContion.joinType)) {
  				ret.add(subContion);
  			}
  		}
  		return ret;
  	}