public Builder addAbnfStrings(java.lang.String value) {
        if (value == null) {
          throw new NullPointerException();
        }
        ensureAbnfStringsIsMutable();
        abnfStrings_.add(value);
        bitField0_ |= 0x00000001;
        onChanged();
        return this;
      }
<pre>
All declarations and rules of an ABNF grammar broken up into multiple
strings that will end up concatenated.
</pre>

<code>repeated string abnf_strings = 1;</code>

@param value The abnfStrings to add.
@return This builder for chaining.
java-speech/proto-google-cloud-speech-v1p1beta1/src/main/java/com/google/cloud/speech/v1p1beta1/SpeechAdaptation.java