@java.lang.Override
  public int getSerializedSize() {
    int size = memoizedSize;
    if (size != -1) return size;

    size = 0;
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(outputUriPrefix_)) {
      size += com.google.protobuf.GeneratedMessageV3.computeStringSize(1, outputUriPrefix_);
    }
    size += getUnknownFields().getSerializedSize();
    memoizedSize = size;
    return size;
  }
<pre>
Required. Google Cloud Storage URI to output directory. For example,
`gs://bucket/directory`. The requesting user must have write permission to
the bucket. The directory will be created if it doesn't exist.
</pre>

<code>string output_uri_prefix = 1 [(.google.api.field_behavior) = REQUIRED];</code>

@return The bytes for outputUriPrefix.
java-translate/proto-google-cloud-translate-v3/src/main/java/com/google/cloud/translate/v3/GcsOutputDestination.java