ashkrit

public class FXService {
    private final CurrencyConverter currencyConverter;
    private final BankService bankService;
    private final double commissionPer;

    public String transfer(Money money, BankAccount destinationAccount, Currency target) {

        String sourceCurrency = money.currency().name();
        String targetCurrency = target.name();

ashkrit

List<Person> p = searchPersonById("100");

        if (p.isEmpty()) {
            System.out.println("No result");
        } else {
            System.out.println("Person" + p.get(0));
        }

ashkrit

  //Address has priority , first home and then Office

Optional<String> address = Stream
                .of(person.getHome().map(Home::getAddress), person.getOffice().map(Office::getAddress))
                .filter(Optional::isPresent)
                .map(Optional::get)
                .findFirst();

        address
                .ifPresent(add -> System.out.println("Contacting at address " + add));

ashkrit

p.getHome().ifPresent(a -> System.out.println("Sending Postal mail " + a.address));

    p.getHome()
                .flatMap(Person.Home::getInsurance)
                .ifPresent(a -> System.out.println("Sending Notification to insurance " + a.agency));

ashkrit

//Don't do this
        System.out.println("Calling Phone " + phone.get());
        System.out.println("Sending Email " + email.get());

        //Use ifPresent to avoid runtime error
        phone.ifPresent(contact -> System.out.println("Sending email to " + contact));
        email.ifPresent(contact -> System.out.println("Calling " + contact));

ashkrit

//Use IfPresent & other cool things
        phone
                .filter(number -> hasOptIn(number))
                .ifPresent(number -> System.out.println("Calling Phone " + number));

        email
                .filter(m -> hasOptIn(m))
                .ifPresent(m -> System.out.println("Sending Email " + m));

ashkrit

//Use Optional
        p.getEmail().ifPresent(email -> System.out.println("Sending email to " + email));
        p.getPhone().ifPresent(phone -> System.out.println("Calling " + phone));

//Optional for Collection or Search type of request
 Optional<Person> person = persons.stream().findFirst();
        person.ifPresent(System.out::println);

ashkrit

public Optional<String> getEmail() {
        return Optional.ofNullable(email);
    }

    public Optional<String> getPhone() {
        return Optional.ofNullable(phone);
    }

ashkrit

 //Address has priority , first home and then Office

        if (p.home != null) {
            System.out.println("Contacted at home address " + p.home.address);
            return; // Magical return for early exit
        }

        if (p.office != null) {
            System.out.println("Contacted at office address " + p.office.address);
            return; // Magical return for early exit

ashkrit

//Nested Property
        if (p.getHome() != null) {
            System.out.println("Sending Postal mail " + p.getHome().address);
        }


        if (p.getHome() != null && p.getHome().getInsurance() != null) {
            System.out.println("Sending Notification to insurance " + p.getHome().getInsurance().getAgency());
        }