gyugyu90

class Headphone {
  double volume = 5;

  void increaseVolume() {
    if (volume == 10) {
      print('최고 볼륨입니다!');
      return;
    }

    volume++;

gyugyu90

abstract class Language {
  factory Language(String languageCode) {
    if (languageCode == 'ko') {
      return Korean();
    }

    return English();
  }

  void sayHello();

gyugyu90

class Logger {
  static final Logger _instance = Logger._internal('MyApplication');

  String prefix;

  Logger._internal(this.prefix);

  factory Logger() {
    return _instance;
  }

gyugyu90

class Coffee {
  String beanType;
  int waterAmount;
  bool hot;
  Syrup? syrup;

  Coffee(this.beanType, [this.waterAmount = 40, this.hot = true, this.syrup]);

  Coffee.iceAmericano(this.beanType, this.waterAmount, [this.syrup])
      : hot = false;

gyugyu90

class Coffee {
  String beanType;
  int waterAmount;
  bool hot;
  Syrup? syrup;

  Coffee(this.beanType,
      [this.waterAmount = 40, this.hot = true, this.syrup]);

  // named constructor

gyugyu90

class Tea {
  final String teaBag;
  Milk? milk;
  late String allergyInfo;

  Tea(this.teaBag, [this.milk]);
}

class Milk {
  String name = "서울우유";

gyugyu90

class Tea {
  final String teaBag;
  Milk? milk;

  Tea(this.teaBag, [this.milk]);

  String getFullName() {
    if (milk != null) {
      return "$teaBag 밀크티";
    }

gyugyu90

class Tea {
  String teaBag = "얼그레이";
  Milk? milk;

  String getFullName() {
    if (milk != null) {
      return "$teaBag 밀크티";
    }

    return "$teaBag 티";

gyugyu90

class Syrup {
  String name;
  int amount;

  Syrup(this.name, this.amount);
}

class Coffee {
  String beanType;
  int waterAmount;

gyugyu90

class Syrup {
  String name;
  int amount;

  Syrup(this.name, this.amount);
}

class Coffee {
  String beanType;
  int waterAmount;