Вроде написал правильно, но ошибку выдаёт.
package com.javarush.task.pro.task18.task1802;
import java.util.ArrayList;
import java.util.Collections;
public class Solution {
public static ArrayList<Student> students = new ArrayList<>();
public static void main(String[] args) {
Collections.addAll(students,
new Student("Иванов", 22),
new Student("Петров", 18),
new Student("Сидоров", 19)
);
Collections.sort(students, new AgeComparator());
for (Student student : students) {
System.out.println(student);
}
}
}