[webbeans-dev] Re: IllegalArgumentException (Was: Re: Updated EJB SPI)

Pete Muir wrote: > > On 17 Mar 2009, at 22:29, Carlo de Wolf wrote: > > ... > >> On another note I would name the >> SessionObjectReference.getReference method getBusinessObject (in >> the likes of SessionContext.getBusinessObject). > > Done > >> And both should throw an NoSuchEJBException if the EJB is already >> removed. > > Done > >> (Note: keep the IllegalStateException for invalid >> businessInterface.) > > Not IllegalArgumentException? I went for IllegalArguementException > > I also did the changes Ken suggested whilst there... Well actually I hate both exceptions in this case. I went for IllegalStateException, because that's how SessionContext.getBusinessObject works, IllegalArgumentException would have been the obvious.

I don't entirely agree with Bloch's guidelines for exception handling (#1). To me the guideline should be: a checked exception whenever an user error is encountered. A precondition on an argument is an user error. So NoSuchBusinessInterfaceException would have been better. Then again this leads to ugly coding (#2), so it might even be better to add boolean SessionContext.isBusinessInterface(Class<?> businessInterface); Then it becomes a programming error again. Ken, does this argument make sense to you? If so, I'll raise it in EJB-EG. > ... > Carlo #1: Effective Java Item 40: Use checked exception for recoverable conditions and run-time exceptions for programming errors #2: EJ Item 41: Avoid unnecessary use of checked exceptions