Is repeatedly instantiating an anonymous class wasteful?

Question

I had a remark about a piece of code in the style of:

Iterable upperCaseNames = Iterables.transform(
    lowerCaseNames, new Function

        

Answer 1

Short answer: No - don't worry.

Long answer: it depends how frequently you're instantiating it. If in a frequently-called tight loop, maybe - though note that when the function is applied it calls String.toUpperCase() once for every item in an Iterable - each call presumably creates a new String, which will create far more GC churn.

"Premature optimization is the root of all evil" - Knuth