@java.lang.Override
  public java.lang.String getCustomClassId() {
    java.lang.Object ref = customClassId_;
    if (ref instanceof java.lang.String) {
      return (java.lang.String) ref;
    } else {
      com.google.protobuf.ByteString bs = (com.google.protobuf.ByteString) ref;
      java.lang.String s = bs.toStringUtf8();
      customClassId_ = s;
      return s;
    }
  }
<pre>
The ID to use for the CustomClass, which will become the final component of
the CustomClass's resource name.

This value should be 4-63 characters, and valid characters
are /[a-z][0-9]-/.
</pre>

<code>string custom_class_id = 3;</code>

@return The customClassId.
java-speech/proto-google-cloud-speech-v2/src/main/java/com/google/cloud/speech/v2/CreateCustomClassRequest.java