I'm not currently doing hot-deploy, but I've always wonder how it could posibly work given that a serialized class might have the underlying base class changed during hot-deploy (e.g. the classic 'run instance' is different than a 'new instance' problem that java throws a ClassCastException from). Its also theoretically problematic (I'm not sure if instanceof or reflection will work properly).
Since this is a very low-level issue (e.g. Java simply doesn't have the facilities to really handle this), how does hot-deply work? The only reliable strategy would appear to be to preserver primatives (since they don't change), maybe preserve 'well-defined' objects (java.util.* is unlikely to change), and discard all the rest. Any thoughts? AT -----Original Message----- From: Peter Beck [mailto:[EMAIL PROTECTED]] Sent: Tuesday, January 29, 2002 7:41 AM To: Orion-Interest Subject: hot redeployment - how to preserve session state? After a forced redeployment of an application on Orion 1.5.3 by touching application.xml my session state seemst to be completely lost. I have set development=true in my global-web-application.xml, and the switch is present in the orion-web.xml in the application- deployment directory. The variables I try to serialize implement the Serializable interface. Some of them are simple JavaBeans, others just Strings. For testing I use a JSP which prints the variables in the session. Before the redeployment everything is there. and when a user is logged in, request.getRemoteUser() gives me the correct user name. After the redeployment session.toString() still gives me the same ID as before, but all variables in the session are gone. Even request.getRemoteUser() == null. What am I missing? Peter
