@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (((bitField0_ & 0x00000001) != 0)) {
      output.writeMessage(1, getPhraseSet());
    }
    if (((bitField0_ & 0x00000002) != 0)) {
      output.writeMessage(2, getUpdateMask());
    }
    if (validateOnly_ != false) {
      output.writeBool(4, validateOnly_);
    }
    getUnknownFields().writeTo(output);
  }
<pre>
If set, validate the request and preview the updated PhraseSet, but do not
actually update it.
</pre>

<code>bool validate_only = 4;</code>

@return The validateOnly.
java-speech/proto-google-cloud-speech-v2/src/main/java/com/google/cloud/speech/v2/UpdatePhraseSetRequest.java