Poornima:
As I said before statements in the init() method are executed *exactly* once
upon servlet initialization. I think you may be expecting the init()
statements to be executed every time a person say logs in to your application.
This is not true. (So, for example, after you restart the server, the init() is
executed once. And that's it till you restart again. Throw in some
System.out.println statements within your init() method as well as your
doPost() and you can check this.) Also if you create a connection in your
init() and then expect to use it in doPost then you are probably declaring it
as a static variable. This means that the *same* connection object is being
shared by every person who accesses your servlet. If you think about this for a
minute you will see that this is certainly not what you want (one person's
result set getting "mixed up" with another person's statement!!). (.Of course
you could make access to that connection object thread-safe by synchronization
blocks, but you may pay a heavy (and unnecessary) price..) Anyway, the bottom
line is, unless you have some special reason to do otherwise, you should have a
connection object for each thread (person) and you can do that easily by
creating (and destroying) it in the doPost/doGet methods... (However, for the
same reason, if you use a connection pool, you should create it in the init().)
As usual, these are only my opinions based on my understanding: I would be
grateful for any corrections..(:-)
Geeta
poornima visvesvaran wrote:
> Hi friend!
>
> I was also having the same problem. After that I
> removed the connection statements in the init()
> method. I created connections only in doPost method.
> It works fine. There is some problem or we have to
> follow some rules if we are using connection
> statements in the init() method. If any body knows,
> please inform us.
>
> Thanks in advance.
>
> Poornima Visvesvaran.
> --- Mittal Shwetabh <[EMAIL PROTECTED]> wrote:
> > Thanks Geeta,
> >
> > Actually I am not destroying the connection created
> > in Init() method (that is
> > the last job)
> > I am destroying only the connection I made in
> > doPost().
> >
> > The flow of application is as follows:
> >
> > 1. It creates a coonection in the init() method and
> > using this connection
> > displays login screen.
> >
> > 2. Now to test whether the login user is
> > authorised(can connect to data base
> > or not)
> > or not I again make a connection in doPost()
> > using the login user as
> > user-id.
> > 3. set a flag which will show whether this
> > connection was successful or not.
> > 4. Close this connection(not the one got using
> > init() method).
> > (In a sense I am making this connection just to
> > check whether this user is
> > authorised
> > user or not in that environment)
> >
> > 5. if flag says the previous connection was
> > successful then do the further
> > processing
> > using the connection made by init() method and
> > the first task is to display
> > a
> > hyper link... which sometimes appears and some
> > times not(the problem)....
> > 6. If I restart the OAS, it works fine. So whenever
> > that exception is thrown,
> > just
> > restart the server and no probs, which is totally
> > unpractical.
> >
> > I hope now u all will be able to get my problem.
> > Please revert back....
> >
> > Regards,
> > Shwetabh
> >
> >
> >
> > Mittal:
> >
> > I am not really clear on what you are trying to do,
> > but I think the problem
> > may be
> > because you are creating the connection in the
> > init() method but destroying it
> > in
> > perhaps a doPost. You may then be trying to access
> > the destroyed connection
> > again
> > in a subsequent doPost, which will not work. This is
> > because code in the init()
> > method is executed just once at initialization time
> > (and not every time a user
> > accesses the servlet via a doPost or doGet.) You may
> > therefore want to get the
> > connection each time in the doPost by creating a
> > connection pool in your init(0
> > method instead. Recent posts to this forum have
> > recommended this link for more
> > information on connection pooling:
> >
> http://www.webdevelopersjournal.com/columns/connection_pool.html
> >
> > Geeta
> >
> > Mittal Shwetabh wrote:
> >
> > > Dear All,
> > >
> > > Can anybody please let me know the reason behind
> > gettng this exception:
> > >
> > > java.sql.SQLException: Io exception: A connection
> > with a remote socket was
> > > reset
> > > by that socket.
> > >
> > > Basically in my application(Java Servlets) I
> > already have a connection
> > object
> > > (got during initialization)
> > > and in between I again need to connect to
> > database and then destroy this
> > > connection with some
> > > other user-id (who will log on through a login
> > screen)to check that user
> > > validity.
> > > And then provide hyper link to application using
> > my existing connection(got
> > > during initialization), if the
> > > user is authorised for it.
> > >
> > > The problem is that sometimes this link does not
> > appear and the above
> > > exception is thrown...
> > > and sometimes it works fine...
> > >
> > > Environment:
> > > OAS8.0.4
> > > AIX4.1.2
> > > Oracle8.1.6
> > > jdbc driver
> > >
> > > Waiting for your reply.
> > >
> > > Regards
> > > Shwetabh Mittal
> >
> >
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