On 2002.01.16 21:49:24 -0500 Bill Pfeiffer wrote: > In my situation, I just have a field that has a unique constraint on it, > but > I would like to allow my user to put in this field whatever they would > like, > as long as there are no duplicates. From a coding perspective, the > constraint failure is THE place to catch this, not with my own attempt to > check the constraint in code. > > I guess what I'm hearing is that Entity Beans are not meant to handle > database constraint errors (or that a constraint violation is > catastrophic > so code to avoid it). Coming from a client server backround where, in > this > case, the issues seem to be the same, I find this kind of odd. If the > violation was a foriegn key constraint, I could kinda understand the > "code > it right so it doesn't happen" stance. But a unique constrained column > value seems like a very reasonable thing to allow the db to determine and > report back to a user.
You did start by saying "referential integrity" ;-) I'm not entirely sure I agree with Scott although I guess philosophically he's right... I do prefer declarative to procedural code. Certainly if the constraint is local it makes sense to check it in the jejb layer. For global constraints such as uniqueness I'm not quite so sure. How about checking for the value first, before you try to insert it, perhaps from a session bean? Try findByUniqueColumn, and take appropriate action if you get something back. david jencks > > Thanks for the response, > > Bill P. > ----- Original Message ----- > From: "David Jencks" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Wednesday, January 16, 2002 8:50 PM > Subject: Re: [JBoss-user] Passing Business Exception to Client > > > > On 2002.01.16 20:25:31 -0500 Bill Pfeiffer wrote: > > > How then do you catch db referential integrity errors and repackage > them > > > in > > > a > > > user friendly manner? I'm not really talking about business logic > per > > > se, > > > but rules that are enforced by the database that need to be > communicated > > > back to the client. > > > > > > Or am I missing some big picture thing? > > > > > > > I always figured if the referential integrity constraints were throwing > > exceptions due to attempts to violate them, that meant I had made a > serious > > logic error in my programming. Perhaps such exceptions need to be > > communicated to the programmer, rather than the client. > > > > david jencks > > > Bill > > > > > > ----- Original Message ----- > > > From: "Dmitri Colebatch" <[EMAIL PROTECTED]> > > > To: "Bill Pfeiffer" <[EMAIL PROTECTED]>; "JBoss-User" > > > <[EMAIL PROTECTED]> > > > Sent: Tuesday, January 15, 2002 12:39 AM > > > Subject: Re: [JBoss-user] Passing Business Exception to Client > > > > > > > > > > in short, you dont. application logic shouldn't be present in > > > > ejbLoad/ejbStore methods. the idea is that you write load/store > stuff > > > once, > > > > and application logic many times. you should throw the exception > from > > > the > > > > method that violated the state (if that is what the exception is > > > about). > > > > > > > > hth > > > > dim > > > > > > > > ----- Original Message ----- > > > > From: "Bill Pfeiffer" <[EMAIL PROTECTED]> > > > > To: "Olaf Strozyk" <[EMAIL PROTECTED]>; "JBoss-User" > > > > <[EMAIL PROTECTED]> > > > > Sent: Tuesday, January 15, 2002 3:54 PM > > > > Subject: Re: [JBoss-user] Passing Business Exception to Client > > > > > > > > > > > > > OK, now I'm confused. Using JBoss 2.4.4, how do I correctly > return > > > > > application level errors from my entity bean's ejbStore method? > Do > I > > > > throw > > > > > my own exception? Does this exception extend RemoteException, > > > Exception? > > > > > Since ejbStore actually overrides its ancestor's method, how do I > > > declare > > > > > that my own exception will be thrown? If I don't declare it as > being > > > > > thrown, I get a compile time error. > > > > > > > > > > Thanks for any clarity on this issue, > > > > > > > > > > Bill Pfeiffer > > > > > ----- Original Message ----- > > > > > From: "Olaf Strozyk" <[EMAIL PROTECTED]> > > > > > To: "danch" <[EMAIL PROTECTED]> > > > > > Cc: <[EMAIL PROTECTED]> > > > > > Sent: Monday, January 14, 2002 7:28 PM > > > > > Subject: Re: [JBoss-user] Passing Business Exception to Client > > > > > > > > > > > > > > > > danch wrote: > > > > > > > EJBException is actually a runtime exception that you use to > > > complain > > > > to > > > > > > > the container when something _really_ wacky happens that you > want > > > to > > > > > > > call a system error. The EJB spec defines a business > exception > > > (AKA > > > > > > > Application Exception) as a different category of exception, > with > > > > > > > different behavior. > > > > > > > > > > > > > > To throw a business exception, define separate classes for > them, > > > > > > > extending RemoteException, then replace your 'throws > > > EJBException' > > > > > > > declaration with your newly defined exception. > > > > > > > > > > > > Hi, > > > > > > > > > > > > sorry to interfere, but let me help out with a "not". The above > has > > > to > > > > > > be "_not_ extending RemoteException". > > > > > > > > > > > > See the spec (Enterprise JavaBeans 2.0, Final Release, 18.1.1): > > > > > > "An application exception class must be a subclass (direct or > > > indirect) > > > > > > of java.lang.Exception. An application exception class must not > be > > > > > > defined as a subclass of the java.lang.RuntimeException or of > the > > > > > > java.rmi.RemoteException." > > > > > > > > > > > > -Olaf > > > > > > > > > > > > > the biggest difference in the container's behavior (aside > from > > > passing > > > > > > > the proper exception back to the client) is that when you > throw > > > an > > > > > > > EJBException, the container marks your transaction > Rollback-only, > > > > while > > > > > > > it _doesn't_ for application exceptions. If you want your > > > transaction > > > > > > > rolled back, you'll need to call setRollbackOnly yourself (on > the > > > > > > > session context). > > > > > > > > > > > > > > -danch > > > > > > > > > > > > > > Bill Pfeiffer wrote: > > > > > > > > > > > > > > > I am having a problem with JBoss 2.4.4 and Tomcat 4.0.1. > When > > > I > > > > > > > > encounter a business logic problem (or sql problem, etc) > and > > > want > > > to > > > > > > > > send it back to the client, I create and throw an > EJBException. > > > The > > > > > > > > problem I am encounter is that I actually recieve, on the > > > client > > > > > > > > (Tomcat) end, an UndeclaredThrowableException which > contains > no > > > info > > > > > on > > > > > > > > the original error. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Probably related is the fact that I get these warnings when > > > > deploying > > > > > my > > > > > > > > beans: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > ------------------------------------------------------ > > > > > > > > > > > > > > > > [ERROR,ContainerFactory] > > > > > > > > Bean : EBSecurityUser > > > > > > > > Method : public abstract String getPassword() throws > > > > RemoteException, > > > > > > > > EJBExcepti > > > > > > > > on > > > > > > > > Section: 9.2.7 > > > > > > > > Warning: The exceptions thrown by methods in the remote > > > interface > > > > must > > > > > > > > be valid > > > > > > > > types for RMI/IIOP > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > [ERROR,ContainerFactory] > > > > > > > > Bean : SBWebSessMgr > > > > > > > > Method : public abstract SBWebSessMgr create() throws > > > > CreateException, > > > > > > > > EJBExcept > > > > > > > > ion, RemoteException > > > > > > > > Section: 6.10.6 > > > > > > > > Warning: The method return values in the home interface > must > be > > > of > > > > > valid > > > > > > > > types f > > > > > > > > or RMI/IIOP. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > [ERROR,ContainerFactory] > > > > > > > > Bean : SBEspeedUtility > > > > > > > > Method : public abstract SBCaseLockHome getSbCaseLockHome() > > > throws > > > > > > > > RemoteExcepti > > > > > > > > on > > > > > > > > Section: 6.10.5 > > > > > > > > Warning: The method return values in the remote interface > must > > > be > > > of > > > > > > > > valid types > > > > > > > > for RMI/IIOP. > > > > > > > > > > > > > > > > --------------------------------------- > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > It appears the I am not returning throwing valid types for > > > RMI/IIOP. > > > > > > > > Any ideas what would cause this? What constitutes a valid > > > RMI/IIOP > > > > > > > > type or what would cause my objects not be considered valid > > > RMI/IIOP > > > > > types? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Thanks for any assistance, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Bill Pfeiffer > > > > > > > > > > > > > > > > > > > > > > _______________________________________________ > > > > > > > JBoss-user mailing list > > > > > > > [EMAIL PROTECTED] > > > > > > > https://lists.sourceforge.net/lists/listinfo/jboss-user > > > > > > > > > > > > _______________________________________________ > > > > > > JBoss-user mailing list > > > > > > [EMAIL PROTECTED] > > > > > > https://lists.sourceforge.net/lists/listinfo/jboss-user > > > > > > > > > > > > > > > _______________________________________________ > > > > > JBoss-user mailing list > > > > > [EMAIL PROTECTED] > > > > > https://lists.sourceforge.net/lists/listinfo/jboss-user > > > > > > > > > > > > _______________________________________________ > > > > JBoss-user mailing list > > > > [EMAIL PROTECTED] > > > > https://lists.sourceforge.net/lists/listinfo/jboss-user > > > > > > > > > _______________________________________________ > > > JBoss-user mailing list > > > [EMAIL PROTECTED] > > > https://lists.sourceforge.net/lists/listinfo/jboss-user > > > > > > > > > > _______________________________________________ > > JBoss-user mailing list > > [EMAIL PROTECTED] > > https://lists.sourceforge.net/lists/listinfo/jboss-user > > > _______________________________________________ > JBoss-user mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/jboss-user > > _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user
