Http Connection Pool

Dear All,
I need to build a connection pool by using the IOUtils library.

I have a website set to download (around 5000) and I need to parallelize the
connection by launching from 10 to 20 connection per time.

I've tried a multithread strategy but it doesn't work soundly.

I'd like to implement something like a queue of connection and I tought
about the apache commons pool libraries.
Is there any implementation of http connection pool?

Thanks in advance

Davide Taibi
http://www.taibi.it