public Builder setDocumentInputConfig(com.google.cloud.translate.v3.DocumentInputConfig value) {
      if (documentInputConfigBuilder_ == null) {
        if (value == null) {
          throw new NullPointerException();
        }
        documentInputConfig_ = value;
      } else {
        documentInputConfigBuilder_.setMessage(value);
      }
      bitField0_ |= 0x00000008;
      onChanged();
      return this;
    }
<pre>
Required. Input configurations.
</pre>

<code>
.google.cloud.translation.v3.DocumentInputConfig document_input_config = 4 [(.google.api.field_behavior) = REQUIRED];
</code>
java-translate/proto-google-cloud-translate-v3/src/main/java/com/google/cloud/translate/v3/TranslateDocumentRequest.java