Java建造者模式

public class Meal {
    private String food;
    private String drink;

    public void setFood(String food){
        this.food = food;
    }
    public String getFood(){
        return food;
    }

    public void setDrink(String drink){
        this.drink = drink;
    }
    public String getDrink(){
        return drink;
    }
}

public abstract class MealBuilder {
    private Meal meal = new Meal();
    public abstract void buildFood();
    public abstract void buildDrink();
    public Meal getMeal(){
        return meal;
    }
}

public class SubMealBuilderA extends MealBuilder {
    @Override
    public void buildFood() {
        System.out.println("This is SubMealBuilderA food!");
    }

    @Override
    public void buildDrink() {
        System.out.println("This is SubMealBuilderA Drink!");
    }
}

public class SubMealBuilderB extends MealBuilder{
    @Override
    public void buildFood() {
        System.out.println("This is SubMealBuilderB food!");
    }

    @Override
    public void buildDrink() {
        System.out.println("This is SubMealBuilderB drink!");
    }
}

public class KFCWaiter {
    private MealBuilder mb = null;

    public KFCWaiter(){

    }

    public KFCWaiter(MealBuilder mb){
        this.mb = mb;
    }

    public void setMealBuilder(MealBuilder mb){
        this.mb = mb;
    }

    public Meal construct(){
        mb.buildDrink();
        mb.buildFood();
        return mb.getMeal();
    }
}

public class BuilderMethod{
    public static void main(String[] args){
        MealBuilder mb_1 = new SubMealBuilderA();
        MealBuilder mb_2 = new SubMealBuilderB();

        KFCWaiter kfc = null;

        kfc = new KFCWaiter(mb_1);
        kfc.construct();

        kfc = new KFCWaiter(mb_2);
        kfc.construct();
    }
}