What is the correct way to sort a list using a Java lambda comparator, and how can I fix the type mismatch error?

[dipen-soni]

If you’re absolutely sure the values returned by getTime() fit safely within an int range (which is rare with timestamps), you could cast them.

But this is not recommended for general use:

messagesByDeviceType.sort((o1, o2) -> (int)(o1.getTime() - o2.getTime()));