code: public final Operation importDocuments(String name) {
  
      ImportDocumentsRequest request = ImportDocumentsRequest.newBuilder().setName(name).build();
      return importDocuments(request);
    }
docs: Imports documents into Google Cloud Firestore. Existing documents with the same name are
  overwritten. The import occurs in the background and its progress can be monitored and managed
  via the Operation resource that is created. If an ImportDocuments operation is cancelled, it is
  possible that a subset of the data has already been imported to Cloud Firestore.
  
  <p>Sample code:
  
  <pre><code>
  try (FirestoreAdminClient firestoreAdminClient = FirestoreAdminClient.create()) {
  DatabaseName name = DatabaseName.of("[PROJECT]", "[DATABASE]");
  Operation response = firestoreAdminClient.importDocuments(name.toString());
  }
  </code></pre>
  
  @param name Database to import into. Should be of the form:
  `projects/{project_id}/databases/{database_id}`.
  @throws com.google.api.gax.rpc.ApiException if the remote call fails