class UserSyncAcceptor extends OperationAcceptor {

    @Override
    protected boolean doOperationsConflict(Operation operation, Operation other) {
        if (operation.getUserList().size() == 1) {
            return false;
        } else if (!operation.getUserList().isEmpty()) {
            return super.doOperationsConflict(operation, other);
        } else {
            return other.getUserList().isEmpty() && doEnvironmentsConflict(operation, other);
        }
    }

    @Inject public  UserSyncAcceptor(OperationRepository operationRepository);

}