public Builder setCustomClassIdBytes(com.google.protobuf.ByteString value) {
      if (value == null) {
        throw new NullPointerException();
      }
      checkByteStringIsUtf8(value);
      customClassId_ = value;
      bitField0_ |= 0x00000002;
      onChanged();
      return this;
    }
<pre>
Required. The ID to use for the custom class, which will become the final
component of the custom class' resource name.

This value should restrict to letters, numbers, and hyphens, with the first
character a letter, the last a letter or a number, and be 4-63 characters.
</pre>

<code>string custom_class_id = 2 [(.google.api.field_behavior) = REQUIRED];</code>

@param value The bytes for customClassId to set.
@return This builder for chaining.
java-speech/proto-google-cloud-speech-v1p1beta1/src/main/java/com/google/cloud/speech/v1p1beta1/CreateCustomClassRequest.java