Adity
I am not sure of any
java package to do this. If your operations are mainly with a single primary key column then you can try loading these CSV's into a suitable datastructure,like Hashmap, where the key is the unique primary key and the value could be an object of a class defined by you. Or anyother better datastructure.
But if your joins and conditions involve many columns or the number of rows are large, then IMHO
you should use something like a
HSQLDB or some inmemory DB to perform your standard SQL operations.
Thanks
Deepak