High Cohesion and a dash of Low coupling

I have two classes.(well there more but i will use two to explain my problem)
Items are processed one by one, by class1, as soon as an item is processed it is sent to class2 for futher processing. Class2 contains queues which stores items sent from class1 while they wait to be processed. I have implemented this, however my problem is as follows:
There is a need for a 'routing system' class which recieves items (one at a time) from class1, works out the shortest queue lenght in class2 and then sends that item to that queue.
The biggest probelm is that the class must be able to handle different situations. E.g able to handle any number of queues, etc.
(Some may be thinking why don't you just write this as method inside class2. The answer is that this 'routing system' is going to be used by the whole program, so it must be made available to all classes without the need for)
Basically High Cohesion and low coupling is the key and this is the reason why I find it difficult to implement this class.
Can anyone help, Thanks.

My suggestion would be to put a manager on top of the queue-set.
So, for a given set of queues, there is a managing-thread that 'receives' the input (output from a prior op) and also responds to the dequeue operation. There are plenty of article on multithreading with multiple producers and multiple consumers. Just use a singleton for the manager.
http://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&q=Java+Multithreading+multiple+producers
http://archive.devx.com/sourcebank/details.asp?resourceNum=123662

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SQL*Net more data to client                155767        0.01          5.69
SQL*Net message from client                174899        0.11        208.21
latch: cache buffers chains                     2        0.00          0.00
latch free                                      4        0.00          0.00
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user4566776 wrote:
My analysis on a particular job trace file drew my attention towards:
1) High rate of Parses instead of Bind variables usage.
But if you look at the text you are using bind variables.
The first query is executed 239 times - which matches the 239 fetches. You cut off some of the useful information from the tkprof output, but the figures show that you're executing more than once per parse call. The time is CPU time spent using a bad execution plan to find no data -- this looks like a bad choice of index, possibly a side effect of the first_rows(1) hint.
2) High fetches and poor number/ low number of rows being processedThe second query is doing a lot of fetches because in 163 executions it is fetching 4.7 million rows at roughly 25 rows per fetch. You might improve performance a little by increasing the array fetch size - but probably not by more than a factor of 2.
You'll notice that even though you record 163 parse calls for the second statement the number of " Misses in library cache during parse" is zero - so the parse calls are pretty irrelevant, the cursor is being re-used.
Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
http://www.jlcomp.demon.co.uk
To post code, statspack/AWR report, execution plans or trace files, start and end the section with the tag {noformat}{noformat} (lowercase, curly brackets, no spaces) so that the text appears in fixed format.
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