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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