Object-based NDC

[He...@amaris.de]

Hello log4jians,

I recently replaced our website's dubious logging-mechanism with log4j.
In the course of doing so I stumbled upon the fact that the NDC 
only accepts Strings as context information.

In the case of our web-application the context information is rather
complex. It consists of all information necessary to answer a
http-request, which are :

- URL parameter
- POST parameter
- current Session state of the user
- an Access-History containing a short information about all requests
  by that user in the current session

To collect all this information and transform it into a string dump
is costly, especially if all this is only necessary if there's really
a log-entry with the current NDC.

Appended is a Version of org.apache.log4j.NDC which accepts it's context
information as Object and uses that Object's toString() to get the
actual information.

The advantage is that you can push an Object-Reference and have it only
evaluated if there is really a call to NDC.get()
(If you replace NDC.pop() with NDC.popObject() which will not evaluate
the context to pop it :-) 

The modified version is compatible with existing client-side-code and
should be running at same speed. (Maybe a bit faster cause it saves
one temporary String per NDC-level and uses only one temporary
StringBuffer if the NDC.get() is called)

Any Comments?

How about including this into log4j?

-- 
have fun,
Sven Helmberger, 
AMARIS Softwareentwicklungsges. mbH

Object-based NDC, second try

[He...@amaris.de]

Here's another version of NDC.java which does not include the fatal
endless recursion in pop().

I really checked the code before posting it, but somehow 
the bug escaped me.

( pop() is not called in our code )

-- 
have fun,
Sven Helmberger,
AMARIS Softwareentwicklungsges. mbH