Convert stream into a for loop java-CodePudding

I kind of need this stream reverse engineered into a for loop. How would it look?

public Optional<Flight> getFlightByFlightNumber(String flightNumber) {
    return flights.stream()
            .filter(flt -> flt.getFlightNumber().equals(flightNumber))
            .findFirst();
}

CodePudding user response：

It will something like this:

public Optional<Flight> getFlightByFlightNumber(String flightNumber) {
    Flight flightByFlightNumber = null;
    for (Flight flight : flights) {
        //You might want to add a null check here before calling equals method, to avoid NullPointerException
        if (flight.getFlightNumber().equals(flightNumber)) {
            flightByFlightNumber = flight;
            // breaking the loop as we found first match
            break;
        }
    }
    return Optional.ofNullable(flightByFlightNumber);
}

CodePudding user response：

Here is one way.

just iterate over the list until the flight is found and return directly in an Optional.
otherwise, return an empty optional when the loop finishes.

public Optional<Flight> getFlightByFlightNumber(String flightNumber) {
    for (Flight flight : flights) {
        if (flight.getFlightNumber.equals(flightNumber)) {
            return Optional.of(flight);
        }
    }
    return Optional.empty();
}