code: public String toQueryString(Criteria criteria, CriteriaQueryBuilder queryBuilder) {
  
      // query builder
      StringBuilder builder = new StringBuilder();
  
      // build the basic query
      builder.append( queryBuilder.getAbsolutePath(criteria, relativePath) );
      builder.append( " IN (");
      
      // We must add each value as a parameter, because not all JPA
      // implementations allow lists or arrays as parameters.
      if( values != null ) {
        for( int i = 0; i < values.length; i++) {
          builder.append( queryBuilder.createPositionalParameter() );
          if( i < values.length - 1 ) {
            builder.append(',');
          }
        }
      }
      builder.append(")");
      
      // return result
      return builder.toString();
    }
docs: /*
  @see org.criteria4jpa.criterion.Criterion#toQueryString(org.criteria4jpa.Criteria, org.criteria4jpa.impl.CriteriaQueryBuilder)