@java.lang.Override
    public final Builder mergeUnknownFields(
        final com.google.protobuf.UnknownFieldSet unknownFields) {
      return super.mergeUnknownFields(unknownFields);
    }
<pre>
Optional. A token to retrieve a page of results. Pass this value in the
ListAdaptiveMtFilesRequest.page_token field in the subsequent call to
`ListAdaptiveMtFiles` method to retrieve the next page of results.
</pre>

<code>string next_page_token = 3 [(.google.api.field_behavior) = OPTIONAL];</code>

@param value The bytes for nextPageToken to set.
@return This builder for chaining.
java-translate/proto-google-cloud-translate-v3/src/main/java/com/google/cloud/translate/v3/ListAdaptiveMtFilesResponse.java