code: public boolean isDone() {
      Operation operation =
          compute.getOperation(operationId, OperationOption.fields(Compute.OperationField.STATUS));
      return operation == null || operation.getStatus() == Status.DONE;
    }
docs: Checks if this operation has completed its execution, either failing or succeeding. If the
  operation does not exist this method returns {@code true}. You can wait for operation
  completion with:
  
  <pre>{@code
  while(!operation.isDone()) {
  Thread.sleep(1000L);
  }
  }</pre>
  
  @return {@code true} if this operation is in {@link Operation.Status#DONE} state or if it does
  not exist, {@code false} if the state is not {@link Operation.Status#DONE}
  @throws ComputeException upon failure