An example of a Java program that sorts a list of employees by their age
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
class Employee implements Comparable<Employee> {
private int age;
private String name;
public Employee(int age, String name) {
this.age = age;
this.name = name;
}
public int getAge() {
return age;
}
public String getName() {
return name;
}
@Override
public int compareTo(Employee o) {
return Integer.compare(this.age, o.age);
}
@Override
public String toString() {
return "Employee [age=" + age + ", name=" + name + "]";
}
}
public class SortEmployees {
public static void main(String[] args) {
List<Employee> employees = new ArrayList<>();
employees.add(new Employee(25, "John"));
employees.add(new Employee(30, "Jane"));
employees.add(new Employee(20, "Bob"));
employees.add(new Employee(35, "Emily"));
System.out.println("Original List: " + employees);
Collections.sort(employees);
System.out.println("Sorted List: " + employees);
}
}
In this example, the Employee
class implements the Comparable
interface and provides a custom implementation of the compareTo()
method. This allows us to sort the employees
list based on the age
field of each Employee
object.
The result is a sorted list of employees that is printed to the console.