How to find Max Date in List<Object>?

Question

Consider a class User

public class User{   int userId;   String name;   Date date; } 

Now I have a List<User> of size 20, how can I find the max date in the list without using manual iterator?

Answer 1

Since you are asking for lambdas, you can use the following syntax with Java 8:

Date maxDate = list.stream().map(u -> u.date).max(Date::compareTo).get(); 

or, if you have a getter for the date:

Date maxDate = list.stream().map(User::getDate).max(Date::compareTo).get();