fromWildcardType,
            to);
        for (int i = 0; i < fromUpperBounds.length; i++) {
          populateTypeMappings(mappings, fromUpperBounds[i], toUpperBounds[i]);
        }
        for (int i = 0; i < fromLowerBounds.length; i++) {
          populateTypeMappings(mappings, fromLowerBounds[i], toLowerBounds[i]);
        }
      }

      @Override