gistfile1.java

  private Single<List<String>> inTransaction(Exception e) throws Exception {
    return client.rxGetConnection().flatMap(conn -> {
      return rxInsertExtraFolks(conn)
        .andThen(uniqueNames(conn))
        .<List<String>>collect(ArrayList::new, List::add)
        .compose(upstream -> e == null ? upstream : upstream.flatMap(names -> Single.error(e)))
        .compose(SQLClientHelper.txSingleTransformer(conn))
        .flatMap(names -> rxAssertAutoCommit(conn).andThen(Single.just(names)))
        .doFinally(conn::close);
    });
  }

  private Single<List<String>> withTransaction(Exception e) {
    return client.rxWithTransaction((Function<SqlClient, Single<List<String>>>) sqlClient ->
      rxInsertExtraFolks(sqlClient)
        .flatMapPublisher(res -> uniqueNames(sqlClient))
        .<List<String>>collect(ArrayList::new, List::add)
        .compose(upstream -> e == null ? upstream : upstream.flatMap(names -> Single.error(e))));
  }