private void ensureCustomClassesIsMutable() {
      if (!((bitField0_ & 0x00000002) != 0)) {
        customClasses_ =
            new java.util.ArrayList<com.google.cloud.speech.v2.CustomClass>(customClasses_);
        bitField0_ |= 0x00000002;
      }
    }
<pre>
A list of inline or referenced PhraseSets.
</pre>

<code>repeated .google.cloud.speech.v2.SpeechAdaptation.AdaptationPhraseSet phrase_sets = 1;
</code>
java-speech/proto-google-cloud-speech-v2/src/main/java/com/google/cloud/speech/v2/SpeechAdaptation.java