Difference in lambda performances?

Question

This is not a duplicate of my question. I checked it and it is more about inner anonymous classes.

I was curious about Lambda expressions and tested the following :

Answer 1

I think the performance difference you're seeing is probably due more to removeIf's use of an iterator internally vs. get and remove in your for loop. The answers in this PAQ have some good information on the benefits of iterators.

bayou.io's answer is spot on, you can see the code for removeIf here it does two passes to avoid shifting the remaining elements over and over.