Listing Ports with android things

listingPorts.java

private void initializeHardware() {
    // Create peripheralManagerService and get GPIO list
    PeripheralManagerService peripheralManagerService = new PeripheralManagerService();
    List<String> portList = peripheralManagerService.getGpioList();
    if (!portList.isEmpty()) {
        try {
            // Initialize GPIOs
            initializeGpios(peripheralManagerService, portList, portList.size() < MAX_RELAYS ? portList.size() : MAX_RELAYS);
        } catch (IOException e) {
            view.showError("An error has ocurred");
        }
    } else {
        view.showError("There are no available ports");
    }
}

private void initializeGpios(PeripheralManagerService peripheralManagerService, List<String> portList, int size)
        throws IOException {
    relays = new ArrayList<>();

    for (int index = 0; index < size; index++) {
        String port = portList.get(index);
        Gpio gpio = peripheralManagerService.openGpio(port);
        gpio.setDirection(Gpio.DIRECTION_OUT_INITIALLY_LOW);
        gpio.setActiveType(Gpio.ACTIVE_LOW);
        gpio.setValue(true); // Set value to TRUE, so lights should be on

        relays.add(new Relay(gpio, port, port));
    }

    // If board doesn´t have max relays, added rest of relays with "none" text to inform to the user
    if (size < MAX_RELAYS) {
        for (int index = size; index < MAX_RELAYS; index++) {
            relays.add(new Relay(null, "NONE"));
        }
    }

    view.showConnectionInformation(relays);
}