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Re: Testing the functionality of sub classes

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From Cecil Westerhof <Cecil@decebal.nl>
Newsgroups comp.lang.java.programmer
Subject Re: Testing the functionality of sub classes
Date Sun, 20 Aug 2017 18:17:02 +0200
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Arne Vajhøj <arne@vajhoej.dk> writes:

> On 8/20/2017 8:49 AM, Cecil Westerhof wrote:
>> Just to satisfy my curiosity I executed (I do not like the formatting,
>> but that is what Eclipse does):
>>      try (
>>              Statement stmt = conn.createStatement();
>>              ResultSet rsOne = stmt.executeQuery("SELECT 12 AS twelve");
>>              ResultSet rsTwo = stmt.executeQuery("SELECT 'Hello World!' AS message")
>>              ) {
>>          System.out.println(stmt);
>>          System.out.println(rsOne);
>>          System.out.println(rsTwo);
>>      }
>>
>> And this gives:
>>      org.sqlite.jdbc4.JDBC4Statement@685f4c2e
>>      org.sqlite.jdbc4.JDBC4ResultSet@7daf6ecc
>>      org.sqlite.jdbc4.JDBC4ResultSet@7daf6ecc
>>
>> So yes, it is like you said: the ResultSet is reused. Is also more
>> logical. I jumped to a conclusion.
>
> As soon as the second executeQuery is running then whatever rsOne
> is pointing to is supposed to be toast.
>
> So SQLite JDBC driver apparently decide to reuse the object for
> the second executeQuery.
>
> Maybe unexpected, but I believe it is OK per spec.

In the description of Statement (copied with spelling mistakes):
    All execution methods in the Statement interface implicitly close
    a statment's current ResultSet object if an open one exists.

Well, maybe you could say it is OK to reuse the old one, but it
certainly does surprise me.

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

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Thread

Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-19 19:40 +0200
  Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-19 21:44 +0200
    Re: Testing the functionality of sub classes Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-19 16:47 -0400
      Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-20 01:30 +0200
        Re: Testing the functionality of sub classes Andreas Leitgeb <avl@logic.at> - 2017-08-20 11:50 +0000
          Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-20 14:49 +0200
            Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-20 15:36 +0200
              Re: Testing the functionality of sub classes Arne Vajhøj <arne@vajhoej.dk> - 2017-08-20 09:46 -0400
                Re: Testing the functionality of sub classes Andreas Leitgeb <avl@logic.at> - 2017-08-20 14:33 +0000
                Re: Testing the functionality of sub classes Arne Vajhøj <arne@vajhoej.dk> - 2017-08-20 11:14 -0400
                Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-20 16:35 +0200
                Re: Testing the functionality of sub classes Arne Vajhøj <arne@vajhoej.dk> - 2017-08-20 11:17 -0400
                Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-20 18:13 +0200
                Re: Testing the functionality of sub classes Arne Vajhøj <arne@vajhoej.dk> - 2017-08-20 12:28 -0400
                Re: Testing the functionality of sub classes Arne Vajhøj <arne@vajhoej.dk> - 2017-08-20 13:06 -0400
                Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-20 19:07 +0200
            Re: Testing the functionality of sub classes Arne Vajhøj <arne@vajhoej.dk> - 2017-08-20 11:21 -0400
              Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-20 18:17 +0200
          Re: Testing the functionality of sub classes v_borchert@despammed.com (Volker Borchert) - 2017-08-21 19:53 +0000
    Re: Testing the functionality of sub classes v_borchert@despammed.com (Volker Borchert) - 2017-08-19 21:15 +0000
      Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-20 01:36 +0200
    Re: Testing the functionality of sub classes Cecil Westerhof <Cecil@decebal.nl> - 2017-08-20 01:22 +0200

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