import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
public class Main {
public static void main(String[] args) {
Map<String, Student> map = new HashMap<>();
map.put("s1", new Student(5, "A"));
map.put("s2", new Student(4, "B"));
map.put("s3", new Student(10, "C"));
map.put("s4", new Student(2, "D"));
Collection<Student> students = map.values();
List<Student> list = new ArrayList<>(students);
Collections.sort(list, new MyComparator());
for (Iterator<Student> it = list.iterator(); it.hasNext();) {
Student stdn = (Student) it.next();
System.out.println("Student id : " + stdn.id);
System.out.println("Student Name : " + stdn.name);
}
}
}
class MyComparator implements Comparator<Student> {
@Override
public int compare(Student s1, Student s2) {
return s1.name.compareTo(s2.name);
}
}
class Student {
int id;
String name;
Student(int id, String name) {
this.id = id;
this.name = name;
}
}