private boolean isExpectedDataSource(String id, DataSource<T> dataSource) {
    if (dataSource == null && mDataSource == null) {
      // DataSource is null when we use directly the Bitmap from the MemoryCache. In this case
      // we don't have to close the DataSource.
      return true;
    }
    // There are several situations in which an old data source might return a result that we are no
    // longer interested in. To verify that the result is indeed expected, we check several things:
    return id.equals(mId) && dataSource == mDataSource && mIsRequestSubmitted;
  }
Returns whether the gesture should be handled by the controller
drawee/src/main/java/com/facebook/drawee/controller/AbstractDraweeController.java