code: public final Operation exportDocuments(DatabaseName name) {
  
      ExportDocumentsRequest request =
          ExportDocumentsRequest.newBuilder().setName(name == null ? null : name.toString()).build();
      return exportDocuments(request);
    }
docs: Exports a copy of all or a subset of documents from Google Cloud Firestore to another storage
  system, such as Google Cloud Storage. Recent updates to documents may not be reflected in the
  export. The export occurs in the background and its progress can be monitored and managed via
  the Operation resource that is created. The output of an export may only be used once the
  associated operation is done. If an export operation is cancelled before completion it may
  leave partial data behind in Google Cloud Storage.
  
  <p>Sample code:
  
  <pre><code>
  try (FirestoreAdminClient firestoreAdminClient = FirestoreAdminClient.create()) {
  DatabaseName name = DatabaseName.of("[PROJECT]", "[DATABASE]");
  Operation response = firestoreAdminClient.exportDocuments(name);
  }
  </code></pre>
  
  @param name Database to export. Should be of the form:
  `projects/{project_id}/databases/{database_id}`.
  @throws com.google.api.gax.rpc.ApiException if the remote call fails