T tmp = buffer[i];
    buffer[i] = buffer[j];
    buffer[j] = tmp;
  }

  /*
   * While the current implementation returns `this`, that's not something we mean to guarantee.
   * Anyway, the purpose of this method is to implement a BinaryOperator combiner for a Collector,
   * so its return value will get used naturally.
   */
  @SuppressWarnings("CanIgnoreReturnValueSuggester")

  }

  @SuppressWarnings("rawtypes") // purpose is to test raw type
  public void testGetSupertype_fromRawClass() {
    assertEquals(
        Types.newParameterizedType(Iterable.class, List.class.getTypeParameters()[0]),
        new TypeToken<List>() {}.getSupertype(Iterable.class).getType());
  }

  @SuppressWarnings({"rawtypes", "unchecked"}) // purpose is to test raw type

  }

  @SuppressWarnings("rawtypes") // purpose is to test raw type
  public void testGetSupertype_fromRawClass() {
    assertEquals(
        Types.newParameterizedType(Iterable.class, List.class.getTypeParameters()[0]),
        new TypeToken<List>() {}.getSupertype(Iterable.class).getType());
  }

  @SuppressWarnings({"rawtypes", "unchecked"}) // purpose is to test raw type

            // or restricted access to system resources. This is acceptable.
            // We primarily want to ensure the method can be called without compilation errors

            // Log the exception for debugging purposes but don't fail the test
            System.out.println("Expected exception in test environment: " + t.getClass().getSimpleName() + ": " + t.getMessage());