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

    size = 0;
    for (int i = 0; i < phraseSets_.size(); i++) {
      size += com.google.protobuf.CodedOutputStream.computeMessageSize(1, phraseSets_.get(i));
    }
    for (int i = 0; i < customClasses_.size(); i++) {
      size += com.google.protobuf.CodedOutputStream.computeMessageSize(2, customClasses_.get(i));
    }
    size += getUnknownFields().getSerializedSize();
    memoizedSize = size;
    return size;
  }
<pre>
A list of inline CustomClasses. Existing CustomClass resources can be
referenced directly in a PhraseSet.
</pre>

<code>repeated .google.cloud.speech.v2.CustomClass custom_classes = 2;</code>
java-speech/proto-google-cloud-speech-v2/src/main/java/com/google/cloud/speech/v2/SpeechAdaptation.java