Multiple Servlet Threads - per HttpSession

          Can there be concurrent Servlet threads on a single HttpSession in cases where
          there are multiple frames on the Browser Window, or if the user has multiple Windows
          open in the same Browser session? Or is it the case that the multiple requests
          on that HttpSession are synchronized to be done in sequence (WebLogic 6.1 as Web
          Server).
          If there can be concurrent threads then how are non-repeatable reads handled for
          objects stored in the HttpSession. For example two threads pick up object A from
          HttpSession, and overwrite each other changes when they set them back in HttpSession.
          Thanks,
          Pradeep

          Thanks but how does that protect against non-repeatable reads?
          Even if there is a synchronized session object in HttpSession still nothing to
          stop from concurrent threads from overwriting each other's settings if the threads
          picked up a value from session object, did some processing and wrote it back.
          (This is almost an optimistic concurrency type scenario)?
          Pradeep
          Alexander Petrushko <[email protected]> wrote:
          >Pradeep Behl wrote:
          >
          >> Can there be concurrent Servlet threads on a single HttpSession in
          >cases where
          >> there are multiple frames on the Browser Window, or if the user has
          >multiple Windows
          >> open in the same Browser session? Or is it the case that the multiple
          >requests
          >> on that HttpSession are synchronized to be done in sequence (WebLogic
          >6.1 as Web
          >> Server).
          >>
          >> If there can be concurrent threads then how are non-repeatable reads
          >handled for
          >> objects stored in the HttpSession. For example two threads pick up
          >object A from
          >> HttpSession, and overwrite each other changes when they set them back
          >in HttpSession.
          >
          >It's up to the application to prevent the threads from stepping on each
          >other when it
          >comes to HttpSession. You can create a thread-safe session class, store
          >your session
          >objects in the instance of that and then have HttpSession store the thread-safe
          >impl.
          >
          >Cheers,
          >
          >Alex
          >
          >

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My support system ensures that I don't look totally incompetent.
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Multiple Servlet Threads - per HttpSession

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