如果一個系統的功能等於其部件的功能之和，
那這個系統就沒有存在的意義，
只有在這個系統組合時能湧現出新的功能，
那才算是組成了一個系統。

public abstract class Drink {
    SugarType sugar;
    IceType ice;

    private Drink(){}

    public Drink(SugarType sugar, IceType ice) {
        this.sugar = sugar;
        this.ice = ice;
    }

    public SugarType getSugar() {
        return sugar;
    }

    public void setSugar(SugarType sugar) {
        this.sugar = sugar;
    }

    public IceType getIce() {
        return ice;
    }

    public void setIce(IceType ice) {
        this.ice = ice;
    }

    enum SugarType{
        REGULAR,LESS,HALF,QUARTER,FREE
    }

    enum IceType{
        REGULAR,EASY,FREE,HOT
    }

}

public class Tea extends Drink {

    TeaType teaType;

    public Tea(SugarType sugar, IceType ice) {
        super(sugar, ice);
    }

    public void setTeaType(TeaType teaType) {
        this.teaType = teaType;
    }

    public TeaType getTeaType() {
        return teaType;
    }

    enum TeaType{
        LEMON,OOLONG,GINGER,HONEY
    }
}

public class Coffee extends Drink {

    private CoffeeType coffeeType;

    public Coffee(SugarType sugar, IceType ice) {
        super(sugar, ice);
    }

    public CoffeeType getCoffeeType() {
        return coffeeType;
    }

    public void setCoffeeType(CoffeeType coffeeType) {
        this.coffeeType = coffeeType;
    }

    enum CoffeeType{
        LATTE,MOCHA,WHITE,BLUE_MOUNTAIN,AMERICANO,ESPRESSO
    }
}

public class DrinkShop {

    public Drink order(String drink,Drink.SugarType sugarType, Drink.IceType iceType){
        drink.toLowerCase();
        switch (drink){
            case "coffee":
                return new Coffee(sugarType,iceType);
            case "tea":
                return new Tea(sugarType,iceType);
            default:
                return null;
        }
    }

}

public class Client {
    @Test
    public void test(){
        DrinkShop drinkShop = new DrinkShop();
        
        //點一杯烏龍茶
        Tea tea = (Tea)drinkShop.order("Tea", Drink.SugarType.FREE, Drink.IceType.EASY);
        tea.setTeaType(Tea.TeaType.OOLONG);
        

        //點一杯美式
        Coffee coffee = (Coffee)drinkShop.order("coffee", Drink.SugarType.QUARTER,Drink.IceType.HOT);
        coffee.setCoffeeType(Coffee.CoffeeType.AMERICANO);
    }
}

public interface Product {
    //敘述自己是什麼商品
    public void describe();
}

public class SaltedFrenchFries implements Product{
    @Override
    public void describe() {
        System.out.println("我是加鹽薯條");
    }
}
public class FrenchFries implements Product{
    @Override
    public void describe() {
        System.out.println("我是無鹽薯條");
    }
}

public class FrenchFriesFactory{
	
    public static FrenchFries creatFrenchFries(String name){
    	if("加鹽".equals(name)) {
        	return new SaltedFrenchFries();
        }
        elis if("無鹽".equals(name)) {
        	return new FrenchFries();
        }
        else {
        	return null;
}	}	}

public class SimpleFactoryTest {
	public static void main(){
    	SaltedFrenchFries sf = 
        	(SaltedFrenchFries)FrenchFriesFactory.creatFrenchFries("加鹽");
        FrenchFries f = 
        	(FrenchFries)FrenchFriesFactory.creatFrenchFries("無鹽");
        sf.describe(); // 我是加鹽薯條
        f.describe(); // 我是無鹽薯條
}	}

public class PizzaStore {
    Pizza orderPizza(String type){
    	Pizza pizza;
    	if(type.equals("cheese")){
	    pizza = new CheesePizza();
    	}else if(type.equals("greek")){
	    pizza = new GreekPizza();
    	}else if(type.equals("pepperoni")){
	    pizza = new PepperoniPizza();
    	}
    	pizza.prepare();
    	pizza.cook();
    	return pizza
    }
}

public class SimplePizzaFactory {
    public Pizza createPizza(String type) {
      Pizza pizza = null;
      if(type.equals("cheese")){
          pizza = new CheesePizza();
      }
      else if(type.equals("greek")){
          pizza = new GreekPizza();
      }
      else if(type.equals("pepperoni")){
          pizza = new PepperoniPizza();
      }
      return pizza;
    }
}

public class PizzaStore {
    SimplePizzaFactory factory;
    public PizzaStore(SimplePizzaFactory factory) { 
		this.factory = factory;
    }
    public Pizza orderPizza(String type) {
      Pizza pizza;
      pizza = factory.createPizza(type);
      pizza.prepare();
      pizza.cook();
      return pizza;
    }
}

public class SimplePizzaFactory {
    public Pizza createPizza(String style, String type) {
	Pizza pizza = null;
	if(style.equals("NY")){
	    if(type.equals("cheese")){
	    	pizza = new NYStyleCheesePizza();
    	    }else...
	    ...
	}else if(style.equals("chicago")){
	    if(type.equals("cheese")){
                pizza = new ChicagoStyleCheesePizza();
            }else...    
            ...
	}
    	return pizza;
    }
}

public class ChicagoPizzaFactory extends SimplePizzaFactory {
    public Pizza createPizza(String type) {
      retrun super.createPizza(type);
    }
}

public class NYPizzaFactory extends SimplePizzaFactory {
    public Pizza createPizza(String type) {
      retrun super.createPizza(type);
    }
}

public class PizzaStore {
    SimplePizzaFactory factory;
    public PizzaStore(SimplePizzaFactory factory) { 
		this.factory = factory;
    }
    public Pizza orderPizza(String type) {
      Pizza pizza;
      pizza = factory.createPizza(type);
      pizza.prepare();
      pizza.cook();
      return pizza;
    }
}

NYPizzaFactory nyFactory = new NYPizzaFactory();
PizzaStore nyStore = new PizzaStore(nyFactory);
nyStore.orderPizza("cheese");

ChicagoPizzaFactory chicagoFactory = new ChicagoPizzaFactory()
PizzaStore chicagoStore = new PizzaStore(chicagoFactory);
chicagoStore.orderPizza("cheese");

public abstract class PizzaStore {
    abstract Pizza createPizza(String type);
    public Pizza orderPizza(String type) {
      Pizza pizza = createPizza(type);
      pizza.prepare();
      pizza.cook();
      return pizza;
    }
}

public class NYPizzaStore extends PizzaStore {
    Pizza createPizza(String item) {
	if (item.equals("cheese")) {
   	    return new NYStyleCheesePizza();
	} else if (item.equals("veggie")) {
	    return new NYStyleVeggiePizza();
	} else if (item.equals("clam")) {
	    return new NYStyleClamPizza();
	} else if (item.equals("pepperoni")) {
	    return new NYStylePepperoniPizza();
	} else return null;
    }
}

public class SoulMate{
    private SoulMate() {}
}

pulic fly(){
	pass
}

pulic fly(){
	pass
}

public class MallardDuck extends Duck {
	public MallardDuck() {
		quackBehavior = new Quack();
		flyBehavior = new FlyWithWings();
	}
	public void display() {
		System.out.println("I'm a real Mallard duck");
	}
}

// Context(Duck): 用ConcreteStrategy的物件 來設定自己的狀態
flyBehavior = new FlyWithWings();

// Strategy(FlyBehavior): 制定所有演算法的共同介面 
// Context透過這個interface呼叫ConcreteStrategy實作的演算法
flyBehavior.fly();