code: @Override
      public AbstractIoBufferEx setAutoExpand(boolean autoExpand) {
          if (!recapacityAllowed) {
              throw new IllegalStateException(
                      "Derived buffers and their parent can't be expanded.");
          }
  
          if (!autoExpand) {
              this.autoExpander = null;
          }
          else {
              throw new IllegalStateException("Use IoBufferEx.setAutoExpander(...) instead");
          }
  
          return this;
      }
docs: {@inheritDoc}