What is the current best practice for all the type conversions necessary in a Java web application?  For example, HttpServletRequest.getParameters(...) returns String[], but Hibernate does not allow String[] to be used in an IN clause for a numeric column.  Therefore I need to convert String[] to Long[] via Long.valueOf().  What is the best way to handle this, short of rewriting in another language?  Do people just create a class full of little static methods to do this?
What is the accepted best practice for Java type conversions?
java;type conversion
If you use a JAX-RS implementation like Jersey, you'll get much improved parameter handling and could map it directly to a List.If you don't want to go that far, you could also pull tricks like using Guava Collections2.transform and a Function<String, Long> on an Arrays.asList view of the array.  Not the most compact way, but each piece is reusable so it wouldn't be so bad.