On Jun 17, 2005, at 6:11 PM, Neal Sanche wrote:
Dain Sundstrom wrote:
On Jun 17, 2005, at 12:04 AM, Neal Sanche wrote:
UserTransaction tx = null;
InitialContext ctx = null;
try {
ctx = new InitialContext();
tx = (UserTransaction)ctx.lookup("UserTransaction");
tx.begin();
chain.doFilter(request, response);
} catch (Throwable e) {
throw new ServletException(e);
} finally {
try {
if (tx != null)
tx.commit();
if (ctx != null)
ctx.close();
} catch (Throwable ex) {
throw new ServletException(ex);
}
}
Is this a servlet filter? I don't believe it is legal to
propagate a tx out of a servlet filter (either down the chain or
up the chain).
-dain
Really? I guess it's not very kosher, but it certainly helps
simplify the code for the pages since while pages render, there's
always a transaction available. There are some obvious side-effects.
Well, I don't think this works on all platforms. I remember
Websphere being very very very strict about transactions in the web
tier. One reason to not wrap an entire web request in a transaction
is you could end up holding the transaction open for a long time as
data is force flushed to a modem user. It is best to read/update all
the data in one isolated tight transaction and then render the page.
To maximize the transaction throughput you want to hold the
transaction open as short as possible.
Having said that. People do this all the time, and it should work in
Geronimo. It is way to common a pattern to not support.
This 'not legal' statement is from a document somewhere Dain?
It is somewhere in the servlet spec. Just search for transaction.
They hardly ever mention transactions so it should be easy to find.
If it isn't in the servlet spec, check the J2EE spec.
-dain
