code: public final ClassifyTextResponse classifyText(Document document) {
  
      ClassifyTextRequest request = ClassifyTextRequest.newBuilder().setDocument(document).build();
      return classifyText(request);
    }
docs: Classifies a document into categories.
  
  <p>Sample code:
  
  <pre><code>
  try (LanguageServiceClient languageServiceClient = LanguageServiceClient.create()) {
  Document document = Document.newBuilder().build();
  ClassifyTextResponse response = languageServiceClient.classifyText(document);
  }
  </code></pre>
  
  @param document Input document.
  @throws com.google.api.gax.rpc.ApiException if the remote call fails