Java tutorial
import java.util.List; import java.time.LocalDate; import java.time.Month; import java.util.Arrays; public class Main { public static void main(String[] args) { List<Employee> persons = Employee.persons(); persons.stream().filter(Employee::isFemale).forEach(p -> p.setIncome(p.getIncome() * 1.10)); System.out.println("After increasing the income: " + persons); } } enum Gender { MALE, FEMALE } class Employee { private long id; private String name; private Gender gender; private LocalDate dob; private double income; public Employee(long id, String name, Gender gender, LocalDate dob, double income) { this.id = id; this.name = name; this.gender = gender; this.dob = dob; this.income = income; } public long getId() { return id; } public void setId(long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public Gender getGender() { return gender; } public boolean isMale() { return this.gender == Gender.MALE; } public boolean isFemale() { return this.gender == Gender.FEMALE; } public void setGender(Gender gender) { this.gender = gender; } public LocalDate getDob() { return dob; } public void setDob(LocalDate dob) { this.dob = dob; } public double getIncome() { return income; } public void setIncome(double income) { this.income = income; } public static List<Employee> persons() { Employee ken = new Employee(1, "Jame", Gender.MALE, LocalDate.of(1970, Month.MAY, 4), 6123.0); Employee jeff = new Employee(2, "Jeff", Gender.MALE, LocalDate.of(1971, Month.JULY, 5), 7112.0); Employee donna = new Employee(3, "Jane", Gender.FEMALE, LocalDate.of(1972, Month.JULY, 9), 8712.0); Employee chris = new Employee(4, "Jodd", Gender.MALE, LocalDate.of(1973, Month.DECEMBER, 6), 1823.0); Employee laynie = new Employee(5, "Janey", Gender.FEMALE, LocalDate.of(1974, Month.DECEMBER, 3), 1234.0); Employee lee = new Employee(6, "Jason", Gender.MALE, LocalDate.of(1975, Month.MAY, 8), 2412.0); // Create a list of persons List<Employee> persons = Arrays.asList(ken, jeff, donna, chris, laynie, lee); return persons; } @Override public String toString() { String str = String.format("(%s, %s, %s, %s, %.2f)", id, name, gender, dob, income); return str; } }