public Builder setFile(
          int index, com.google.protobuf.DescriptorProtos.FileDescriptorProto value) {
        if (fileBuilder_ == null) {
          if (value == null) {
            throw new NullPointerException();
          }
          ensureFileIsMutable();
          file_.set(index, value);
          onChanged();
        } else {
          fileBuilder_.setMessage(index, value);
        }
        return this;
      }