Control Interceptor SPI missing throwable for event dispatching

• Key: BEEHIVE-1051
• Type: Bug
• Status: Resolved
• Resolution: Fixed
• Priority: Major
• Assignee: Kenneth Tam
• Reporter: Xibin Zeng
• Component/s: Controls
• Affects Version/s: 1.0.1
• Fix Version/s: 1.0.1

Description

There are 4 methods on the org.apache.beehive.controls.spi.svc.Interceptorinterface.

For a control operation, preInvoke/postInvoke are called before and after the operation, respectively. The postInvoke callback contains the exception that the operation threw. For preEvent/postEvent, which is called before and after control event dispatching, however, there is no exception information passed to the postEvent callback. This looks inconsistent to me.

Imagine that you need to enforce J2EE transaction behaviors using these interceptors (i.e. rollback a transaction in case of a system exception), you will need to know what exception has been generated as the result of invoking the operation or event callback. You could do this for your control operations, but not event callbacks, since the exception caught during event callback isn't passsed to the interceptor.

In my humble opinion, I think we should make preInvoke/postinvoke and preEvent/postEvent API's symmetric.

Comments

[Xibin Zeng]

Correction - the name of the interface is

org.apache.beehive.controls.spi.svc.Interceptor

[Kenneth Tam]

Good catch. Here's a proposed fix that makes postEvent symmetric with postInvoke (adding the return value and throwable to the postEvent signature). Does this solve your issue, Xibin?

[Kenneth Tam]

Fixed as of rev 372680