one simple question to ask

[blust1984]

Hello all, I am new in AOP, I have one question, is that so that to Log event, for example what time user login when user log out, which service or method is used by a certain user etc. To log such events , AOP is a good choice? Another question can the log event information be output as a file like pdf file?

[Andreas Senft]

Hello all, I am new in AOP, I have one question, is that so that to Log event, for example what time user login when user log out, which service or method is used by a certain user etc. To log such events , AOP is a good choice?

Yes. You can decorate method invocations via AOP to do things before and/ or after as you wish. Logging, especially for auditing and tracing purposes, is a quite common usecase for AOP.

Another question can the log event information be output as a file like pdf file?

In theory yes. Though the overhead would be big and I am not sure whether it is possible to dynamically create PDF documents. A better solution would be to create plain text files of limited size (e.g. using a RollingFileAppender) and convert these to PDF later.

[Jörg Heinicke]

I am not sure whether it is possible to dynamically create PDF documents.

Of course that's possible Spring itself comes with an AbstractPdfView (which won't be usable here). And Cocoon offers a FOPSerializer since years.

So it's more or less only a question of integration. But I would definitely not add it to the logging since it's a PDF rendering is really resource intensive process.

Jörg

[Andreas Senft]

Of course that's possible Spring itself comes with an AbstractPdfView (which won't be usable here). And Cocoon offers a FOPSerializer since years.

Hi Jörg,
yes I have been aware of that, but I did express myself unclear. With "dynamically" I meant to dynamically append to an existing PDF document as required by logging. What I am not sure is, whether it would be as simple as just adding a line like in a text file.

So it's more or less only a question of integration. But I would definitely not add it to the logging since it's a PDF rendering is really resource intensive process.

Indeed. Irrespective of the fact how simple it might be, I also do not think that it would be a good idea.

Regards,
Andreas

[Jörg Heinicke]

What I am not sure is, whether it would be as simple as just adding a line like in a text file.

I think iText is quite good in this regard (modifying PDFs). We use it for splitting huge PDFs in multiple files and adding preview watermarks to preview versions. But since I did not implement it I can't tell so much about it.

Jörg