code: public FwDbDirection assistDbDirection() {
          if (dbDirection != null) {
              return dbDirection;
          }
          synchronized (this) {
              if (dbDirection != null) {
                  return dbDirection;
              }
              final FwDbDirection direction = createDbDirection();
              prepareDbDirection(direction);
              dbDirection = direction;
          }
          return dbDirection;
      }
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