code: @BetaApi(
        "The surface for long-running operations is not stable yet and may change in the future.")
    public final OperationFuture<Empty, KnowledgeOperationMetadata> deleteDocumentAsync(
        DocumentName name) {
  
      DeleteDocumentRequest request =
          DeleteDocumentRequest.newBuilder().setName(name == null ? null : name.toString()).build();
      return deleteDocumentAsync(request);
    }
docs: Deletes the specified document.
  
  <p>Operation &lt;response: [google.protobuf.Empty][google.protobuf.Empty], metadata:
  [KnowledgeOperationMetadata][google.cloud.dialogflow.v2beta1.KnowledgeOperationMetadata]&gt;
  
  <p>Sample code:
  
  <pre><code>
  try (DocumentsClient documentsClient = DocumentsClient.create()) {
  DocumentName name = DocumentName.of("[PROJECT]", "[KNOWLEDGE_BASE]", "[DOCUMENT]");
  documentsClient.deleteDocumentAsync(name).get();
  }
  </code></pre>
  
  @param name The name of the document to delete. Format: `projects/&lt;Project
  ID&gt;/knowledgeBases/&lt;Knowledge Base ID&gt;/documents/&lt;Document ID&gt;`.
  @throws com.google.api.gax.rpc.ApiException if the remote call fails