I\'m implementing compareTo()
method for a simple class such as this (to be able to use Collections.sort()
and other goodies offered by the Java pl
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Comparator;
public class TestClass {
public static void main(String[] args) {
Student s1 = new Student("1","Nikhil");
Student s2 = new Student("1","*");
Student s3 = new Student("1",null);
Student s11 = new Student("2","Nikhil");
Student s12 = new Student("2","*");
Student s13 = new Student("2",null);
List list = new ArrayList();
list.add(s1);
list.add(s2);
list.add(s3);
list.add(s11);
list.add(s12);
list.add(s13);
list.sort(Comparator.comparing(Student::getName,Comparator.nullsLast(Comparator.naturalOrder())));
for (Iterator iterator = list.iterator(); iterator.hasNext();) {
Student student = (Student) iterator.next();
System.out.println(student);
}
}
}
output is
Student [name=*, id=1]
Student [name=*, id=2]
Student [name=Nikhil, id=1]
Student [name=Nikhil, id=2]
Student [name=null, id=1]
Student [name=null, id=2]