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From: Andreas Leitgeb <avl@logic.at>
Newsgroups: comp.lang.java.programmer
Subject: Re: Testing the functionality of sub classes
Date: Sun, 20 Aug 2017 11:50:34 -0000 (UTC)
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Cecil Westerhof <Cecil@decebal.nl> wrote:
> For example: when creating a new ResultSet through a Statement the
> previous generated should be closed. With the JDBC driver I use for
> SQLite3 the old ResultSet is not closed, but becomes a copy from the
> last generated.

Are you sure about the "copy"? I'd rather expect(*) that the driver 
re-uses the particular ResultSet instance and returns the same ref
again.  (*: that is: based on your posted observations. Usually, 
instance re-use is frowned upon, like premature optimisation, but then
again, DB driver vendors might have optimised it "well-maturely".)

To verify (or disprove) it, you could run it in e.g. eclipse, and see
if the same (or a new) "id" appears when you execute another query on
the same Statement.

Even without a debugger, you could print out the System.identityHashCode 
for the "two" returned ResultSet references.