If we would like to implement all tables of the WWW-MIB additional functionality would have to be provided. Here is a rather rough list:

1. Create one object for each document containig access/byte counters - not just for the last n, but all.

2. Read list of last n documents from separate buffer, when WwwDocLastNTable is locked.

3. Decrease lock (timer) and create and purge buckets in time interval.

The Lock Mechanism

I spent a quick thought on how to implement the lock mechanism for the WwwDocLastNTable and arrived in assuming I should create a WwwDocLastNTableImpl class that stores the information instead of manipulating the table from outside and storing update information elsewhere. The latter would take rather sophisticated case distinction and a sort of "list of changes" while the new class could easiely copy its internal data and shadow the changes with this copy.

Frank on the other hand suggested to refrain from using a derived table class because there is no necessity to and this should not be the usual way of solving problems.

Bucket Problems

I realized that I could use a Vector of either WwwDocAccessTopNEntryImpl or WwwDocBytesTopNEntryImpl objects to keep a complete list of all documents. These objects would be copied to or placed in the tables when they would become one of the top n documents. But this approach would not help sorting out the rows of a bucket in the top n document statistics. Buckets are filled over a configurable time interval. A new bucket is created when this interval expires and the computed statistics are filled in. If the number of configured buckets exceeds the oldest bucket is removed. The buckets take the form of an additional index in the WwwDocBucketTable, WwwDocAccessTopNTable and WwwDocBytesTopNTable.

Later Frank and I decided to concentrate on the minimal conformance and skip this issue especially to avoid a complex bucket handling. The code is intended to serve as an example and therefore we strive for simplicity and easy understanding of JAX applications, not for full WWW-MIB conrformance.