Comparator with Lambda Examples

In this example we will make use of Landba expression to sort students by name using Comparator

public class Student {

    public Student(int studentId, String studentName) {
        this.studentId = studentId;
        this.studentName = studentName;

    private int studentId;
    private String studentName;
    private int studentAge;
    private boolean studentGender;

    public int getStudentId() {
        return studentId;

    public void setStudentId(int studentId) {
        this.studentId = studentId;

    public String getStudentName() {
        return studentName;

    public void setStudentName(String studentName) {
        this.studentName = studentName;

    public int getStudentAge() {
        return studentAge;

    public void setStudentAge(int studentAge) {
        this.studentAge = studentAge;

    public boolean isStudentGender() {
        return studentGender;

    public void setStudentGender(boolean studentGender) {
        this.studentGender = studentGender;

    public String toString() {
        return "Student{" +
                "studentId=" + studentId +
                ", studentName='" + studentName + '\'' +

import java.util.ArrayList;
import java.util.Comparator;
import java.util.List;

public class Main {

    public static void main(String[] args) {

        List<Student> students = new ArrayList<>();
        students.add(new Student(1, "Sam"));
        students.add(new Student(2, "Mike"));
        students.add(new Student(3, "Alex"));
        students.add(new Student(3, "Richard"));
        students.add(new Student(3, "Andrew"));
        students.add(new Student(3, "Andy"));

        Comparator<Student> sortByName = (Student s1, Student s2)
                -> s1.getStudentName().compareTo(s2.getStudentName());

        System.out.println("Before Sort: "+ students);
        System.out.println("After Sort: "+ students);

Before Sort: [Student{studentId=1, studentName='Sam'}, Student{studentId=2, studentName='Mike'}, Student{studentId=3, studentName='Alex'}, Student{studentId=3, studentName='Richard'}, Student{studentId=3, studentName='Andrew'}, Student{studentId=3, studentName='Andy'}]

After Sort: [Student{studentId=3, studentName='Alex'}, Student{studentId=3, studentName='Andrew'}, Student{studentId=3, studentName='Andy'}, Student{studentId=2, studentName='Mike'}, Student{studentId=3, studentName='Richard'}, Student{studentId=1, studentName='Sam'}]

Try Out Code2care Dev Tools:


Code2care is an initiative to publish and share varied knowledge in programming and technical areas gathered during day-to-day learnings and development activities.

Students and software developers can leverage this portal to find solutions to their various queries without re-inventing the wheel by referring to our easy to understand posts. Technical posts might include learnings, tutorials, trouble-shooting steps, video tutorials, code snippets, how-to, blogs, articles, etc.

🎉 We are celebrating the 10th years of Code2care! Thank you for all your support!

We strongly support Gender Equality & Diversity.