Hi Community,
+ I have been reading various threads related to monitoring/exceptions/logging: the old approach (@Monitor annotation and java based logging), and the most recent one you have started discussing about using AOP. + I am neither a Tuscany nor an AOP expert, but I am interested on these topics and wanted to make some comments: - As you know, there are various advantages in using aspects in crosscutting functionalities such as the separation of concerns (i.e. not mixing monitoring and business code). But particularly on handling exceptions there are some specific advantages as shown in http://citeseer.ist.psu.edu/538140.html . - But there are also some problems on using AOP: a- If business code is changing, surely you should keep changing defined join points (but in the case of not using AOP if code changes, either monitoring code should be moved/changed and maybe in a more complex way). In this context, I think the best place where to set join points would be on the SPI component (if possible). b- Another problem with exception handling with AOP -as far as I know- is that you can set joint points to be classes or methods, but not to be arbitrary blocks of code (much used in exception handling). Anyway this restriction seems to be changing in some AOP implementations. + Also I would like to know if you are actually working on the AOP approach, and to make you other specific questions: - I have read that you are planning to monitor plug points on composite, component start/stop, service invocation, etc. Referring to them, the scope of the monitoring would be within a single runtime, or are you thinking on monitoring more general "domain" metrics? - Much monitoring information can be obtained from exceptions. So if exception handling can be well achieved with aspects, either aspects can be used as a monitoring mechanism (and not only for exceptions). In this context, I would like to know if you are planning to publish the monitoring events in some way, or the main intention is just to log the monitoring data? Thanks and Best Regards, Cristian Fiorentino.
