public static function tableName()
 {
     if (is_null(static::$_tableName)) {
         $base_a = StringHelper::basename(static::aClass());
         $base_b = StringHelper::basename(static::bClass());
         $base = $base_a < $base_b ? $base_a . $base_b : $base_b . $base_a;
         static::$_tableName = '{{%' . Inflector::camel2id($base, '_') . '}}';
     }
     return static::$_tableName;
 }
 public static function setTableName($tblName)
 {
     static::$_tableName = $tblName;
 }