Re: Understanding Implements

["Fred Kulack" <kulack@xxxxxxxxxx>]

On 03/20/2001 at 10:38:28 AM, "Eyers, Daniel" <daniel.eyers@honeywell.com>
wrote:
hmmm... can you explain what the following is doing?

public class myClass extends HttpServlet implements SingleThreadModel

I know I have a class called myClass that inherits from HttpServlet.  I
also
know that implementing SingleThreadModel changes the way the HttpServlet is
handled by WAS.
---- end of excerpt ---
This is an awesome little trick.
Note that the SingleThreadModel has no methods defined on it.
However, somewhere in the bowels of the servlet engine, when your
servlet is constructed, the code will do something like this:

 if (obj instanceof SingleThreadModel) {
  // ensure no other thread is running it, dispatch in
  // a single thread
 }
 else {
   // dispatch in a new thread immediately
 }

Its a convenient way to make your object a certain TYPE of object.
I.e. one that can only handle single threads.


"The stuff we call "software" is not like anything that human society
  is used to thinking about. Software is something like a machine, and
  something like mathematics, and something like language, and
  something like thought, and art, and information...
  but software is not in fact any of those other things."
Bruce Sterling - The Hacker Crackdown

Fred A. Kulack  -  AS/400e  Java and Java DB2 access, Jdbc, JTA, etc...
IBM in Rochester, MN  (Phone: 507.253.5982   T/L 553-5982)
mailto:kulack@us.ibm.com   Personal: mailto:kulack@bresnanlink.net
AOL Instant Messenger: Home:FKulack  Work:FKulackWrk

+---
| This is the JAVA/400 Mailing List!
| To submit a new message, send your mail to JAVA400-L@midrange.com.
| To subscribe to this list send email to JAVA400-L-SUB@midrange.com.
| To unsubscribe from this list send email to JAVA400-L-UNSUB@midrange.com.
| Questions should be directed to the list owner: joe@zappie.net
+---