RE: Stateless Session Beans
I believe that the servletContext which can meet the bill for you. Have a servlet initialize on loading the application, you can control that in the web.xml. Whenever the slsb is initialized, pass the servelet context, and get your application class with a servletContext.getAttribute(myClass). You can also get a env reference, and let the slsb get the reference (if its a simple object you want). -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of SCOTT FARQUHAR Sent: Wednesday, May 02, 2001 10:48 PM To: Orion-Interest Subject: Stateless Session Beans I'm hoping that someone can help me with this. Can you have a stateless session bean that actually has class variables? Ie I want to have a variable that is loaded once per application, and then accessed by all the whole application. I know that SLSB are pooled and created and destroyed at will - but will they be created with the variable containing a value? Any thoughts are much appreciated. Scott
RE: Stateless Session Beans
Scotty, What is the need for this? Any stateless session variable can have a normal variable that's initialised in the ejbActivate() and ejbCreate() methods. static variables are fugly in a distributed environment because they're only per JVM - remember this ! -mike -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of SCOTT FARQUHAR Sent: Thursday, May 03, 2001 3:48 PM To: Orion-Interest Subject: Stateless Session Beans I'm hoping that someone can help me with this. Can you have a stateless session bean that actually has class variables? Ie I want to have a variable that is loaded once per application, and then accessed by all the whole application. I know that SLSB are pooled and created and destroyed at will - but will they be created with the variable containing a value? Any thoughts are much appreciated. Scott
RE: Stateless session beans reuse
h ... I understand the case where, for instance, the field holds something that uses system resources like an open file-based stream. However, in this case the goal is to eliminate the repeated lookups for home interfaces. There would be little savings if we get the home interfaces in the ejbCreate and nulled them in ejbRemove, but the interesting question for us is 'will the field still be valid, and if not how can one tell so it can be made valid again?' .. so we can safely lazy initialize those fields. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Jason Boehle Sent: Wednesday, December 13, 2000 4:28 PM To: Orion-Interest Subject: RE: Stateless session beans reuse My understanding is that the fields will not be set to null. Instance variables are useful in stateless session beans to hold references to "global" objects/resources that are used over and over again. You can allocate/release the variables in ejb[Post]Create()/ejbRemove(). Please, someone else tell me if I am wrong! :) Jason Boehle [EMAIL PROTECTED] -Original Message- From: John D'Ausilio [mailto:[EMAIL PROTECTED]] Sent: Wednesday, December 13, 2000 1:42 PM To: Orion-Interest Subject: Stateless session beans reuse Stateless session beans are clearly allowed to have instance variables (fields). A client of a stateless session bean cannot assume that he has the same bean instance for each method call. Assume we have a stateless session bean, which holds some fields storing various home interfaces. Gary (my co-worker) and I disagree in interpreting the EJB spec on what happens to those fields between method calls, specifically with respect to lazy initialization. My assumption is that those fields will be set to null between method calls, Gary assumes that the field may hold valid information (in which case lazy initialization dosn't occur). Comments? (we discussed doing a test, but that would only prove what Orion does ...) john d
RE: Stateless session beans reuse
My understanding is that the fields will not be set to null. Instance variables are useful in stateless session beans to hold references to "global" objects/resources that are used over and over again. You can allocate/release the variables in ejb[Post]Create()/ejbRemove(). Please, someone else tell me if I am wrong! :) Jason Boehle [EMAIL PROTECTED] -Original Message- From: John D'Ausilio [mailto:[EMAIL PROTECTED]] Sent: Wednesday, December 13, 2000 1:42 PM To: Orion-Interest Subject: Stateless session beans reuse Stateless session beans are clearly allowed to have instance variables (fields). A client of a stateless session bean cannot assume that he has the same bean instance for each method call. Assume we have a stateless session bean, which holds some fields storing various home interfaces. Gary (my co-worker) and I disagree in interpreting the EJB spec on what happens to those fields between method calls, specifically with respect to lazy initialization. My assumption is that those fields will be set to null between method calls, Gary assumes that the field may hold valid information (in which case lazy initialization dosn't occur). Comments? (we discussed doing a test, but that would only prove what Orion does ...) john d
