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Re: Is this the way to work with try with resources

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Andreas Leitgeb <avl@logic.at> writes:

> Cecil Westerhof <Cecil@decebal.nl> wrote:
>> I had there the following function:
>>     public ResultSet executeQuery(String query) throws SQLException {
>>         return conn.createStatement().executeQuery(query);
>>     }
>> but I now changed that to:
>>     public ResultSet executeQuery(String query) throws SQLException {
>>         try (Statement stmt = conn.createStatement()) {
>>             return stmt.executeQuery(query);
>>         }
>>     }
>> This should take care of the leakage.
>
> I fear, next trouble is right ahead.
>
> try doesn't only close it's resource on failure, but also on completion!
>
> That means, it will (because closing the statement will also close the
> ResultSet) return an already closed ResultSet.

I have in my code:
    private static void displayOldestUsed() {
        try (ResultSet rsOldest = sqlite3Conn.executeQuery(OLDEST_USED)) {
            if (rsOldest.next()) {
                giveMessage("Oldest used: " + rsOldest.getString("used") + ".");
            }
        } catch (SQLException e) {
            giveError("Error in displayOldestUsed");
            e.printStackTrace();
            fatalError("");
        }
    }

And rsOldest.getString("used") gives the result I would expect. Or am
I just ‘lucky’?

-- 
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof

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Thread

Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-08 13:26 +0200
  Re: Is this the way to work with try with resources Martin Gregorie <martin@address-in-sig.invalid> - 2017-08-08 12:51 +0000
    Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 07:10 +0200
  Re: Is this the way to work with try with resources Patrick Roemer <sangamon@netcologne.de> - 2017-08-08 18:29 +0200
    Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 07:20 +0200
    Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 07:16 +0200
  Re: Is this the way to work with try with resources Patrick Roemer <sangamon@netcologne.de> - 2017-08-08 19:30 +0200
    Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 06:49 +0200
    Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 07:01 +0200
    Re: Is this the way to work with try with resources Patrick Roemer <sangamon@netcologne.de> - 2017-08-09 15:39 +0200
  Re: Is this the way to work with try with resources Arne Vajhøj <arne@vajhoej.dk> - 2017-08-08 21:25 -0400
    Re: Is this the way to work with try with resources Arne Vajhøj <arne@vajhoej.dk> - 2017-08-08 21:36 -0400
      Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 07:29 +0200
        Re: Is this the way to work with try with resources Arne Vajhøj <arne@vajhoej.dk> - 2017-08-09 20:53 -0400
          Re: Is this the way to work with try with resources Arne Vajhøj <arne@vajhoej.dk> - 2017-08-09 23:03 -0400
    Re: Is this the way to work with try with resources Arne Vajhøj <arne@vajhoej.dk> - 2017-08-08 21:48 -0400
    Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 07:24 +0200
  Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 06:26 +0200
    Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 08:30 +0200
    Re: Is this the way to work with try with resources Andreas Leitgeb <avl@logic.at> - 2017-08-09 09:40 +0000
      Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 12:56 +0200
        Re: Is this the way to work with try with resources Andreas Leitgeb <avl@logic.at> - 2017-08-09 16:51 +0000
          Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 19:37 +0200
            Re: Is this the way to work with try with resources Andreas Leitgeb <avl@logic.at> - 2017-08-09 19:51 +0000
              Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 22:20 +0200
                Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 23:17 +0200
          Re: Is this the way to work with try with resources Patrick Roemer <sangamon@netcologne.de> - 2017-08-09 22:08 +0200
        Re: Is this the way to work with try with resources Arne Vajhøj <arne@vajhoej.dk> - 2017-08-09 18:07 -0400
    Re: Is this the way to work with try with resources Arne Vajhøj <arne@vajhoej.dk> - 2017-08-09 18:05 -0400
  Re: Is this the way to work with try with resources Cecil Westerhof <Cecil@decebal.nl> - 2017-08-09 06:39 +0200

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