Re: RE: Error in servlet

On Fri, 15 Sep 2000, Andreas Tille wrote:

> On Thu, 14 Sep 2000, chris markiewicz wrote:
>
> > could this be a servlet/thread issue?  i cannot tell from the code snippet,
> Solved.  I really stupidly forgot an rs.next() :-(((.
>
> > but remember that variables in a servlet with class scope are essentially
> > static.  (i am guessing that query, rs, stmt, etc are all class scope.  this
> > is very dangerous, in the programming sense of the word...)  i've had
> > similar (but not the same) problems before.  as a general rule, i NEVER put
> > a class scope variable in a servlet unless i really mean to.
> Well, that might be true for query and rs and I'll change that, but
> in my opinion
>
> public class ServletSQLClass
> {
>   private Connection          con;
>   private Statement           stmt;
>
>   ...
>   con = DriverManager.getConnection(url,user,passwd);
>   stmt = con.createStatement();
>   ...
> }
>
> con and stmt have to be class scope to hold the connection to the
> database and don't have to reopen over and over.  Or did I understand
> something wrong?

IMHO, only Connection should be of class scope, as you can create as many
Statement/PreparedStatements as you want.

Peter

--
Peter T Mount peter@retep.org.uk http://www.retep.org.uk
PostgreSQL JDBC Driver http://www.retep.org.uk/postgres/
Java PDF Generator http://www.retep.org.uk/pdf/