Input
Output
import java.util.*; public class ComparableExample { public static void main(String[] args) { List<Student> list = new ArrayList<>(); list.add(new Student(102, "Alice")); list.add(new Student(101, "Bob")); list.add(new Student(103, "Charlie")); Collections.sort(list); // uses compareTo() for (Student s : list) { System.out.println(s.id + " - " + s.name); } } }