[squid-users] index key generation mechanism?

hi all:

For the file of "somejs.js", there are two urls referring to it, for
example: url1 is "http://www.a.com/somejs.js" and url2 is
"http://www.a.com/somejs.js".

by default, squid would use the above urls to generate certain key
that would be used as index key to write/read the somejs.js file
to/from memory.

My question is that: could I affect the index key generation, so that
squid could save the somejs.js file in memory only one object. for
example, for url1, we can trim "http://www.a.com/somejs.js" to
"somejs.js" and "http://www.a.com/somejs.js" to "somejs.js", then the
key would be "somejs.js", e.g. use the file name (or some variants
based on it) as index key. this way, we can "save" the two different
urls (the referred files have the same content) as only one object in
Squid.

is it possible?

thanks in advance!

-- 
Best Regards
rmn190