1. 工厂模式

假如有家食品厂在生产食物，先创建一个接口

public interface Food {
    void make();
}

这食品厂能制造饮料（具体产品类）

public class Drinks implements Food {
    @Override
    public void make() {
        System.out.println("生产饮料");
    }
}

也可以制造饼干（具体产品类）

public class Biscuits implements Food {
    @Override
    public void make() {
        // TODO Auto-generated method stub
        System.out.println("生产饼干");
    }
}

开工厂为了接单赚钱嘛，这里相当于订单，当别人下了订单类型，生产对应的产品（工厂类）

public class FoodFactory {
    public static final int DRINKS = 0;
    public static final int BISCUITS = 1;
    
    public Food getPlayer(int type) {
        switch (type) {
        case DRINKS:
            return new Drinks();
        case BISCUITS:
            return new Biscuits();
        default:
            return null;
        }
    }
}

接到饮料单子，开始生产饮料了~

public static void main(String[] args) {
    FoodFactory factory = new FoodFactory();
    Food food = factory.getPlayer(FoodFactory.DRINKS);
    food.make();
}

2. 工厂方法模式

先写一个食品厂

public interface FoodFactory {
    public Food getFood();
}

这个食品厂的饮料生产线

public class DrinksFactory implements FoodFactory{
    @Override
    public Food getFood() {
        // TODO Auto-generated method stub
        return new Drinks();
    }

还有饼干类的生产线

public class BiscuitsFactory implements FoodFactory{
    @Override
    public Food getFood() {
        // TODO Auto-generated method stub
        return new Biscuits();
    }
}

接到哪种订单就new哪种类型的生产线就行啦~

public static void main(String[] args) {
    // TODO Auto-generated method stub
    FoodFactory factory = new BiscuitsFactory();
    Food food = factory.getFood();
    food.make();
}

3. 抽象工厂

假设现在有家衣服店在卖衣服

先定义衣服款式类型

public interface Style {
    void type();
}

public class LongSleeve implements Style {
    @Override
    public void type() {
        System.out.println("长袖");
    }
}

public class ShortSleeve implements Style {
    @Override
    public void type() {
        System.out.println("短袖");
    }
}

还有衣服的颜色

public interface Color {
    void fill();
}

public class Red implements Color {
    @Override
    public void fill() {
        System.out.println("红色");
    }
}

public class Blue implements Color {
    @Override
    public void fill() {
        System.out.println("蓝色");
    }
}

定义这件adidas的款式以及颜色

public class AdidasFactory implements AbstractFactory{
    @Override
    public Style getStyle() {
        return new LongSleeve();
    }
    @Override
    public Color getColor() {
        return new Red();
    }
}

还有特步的款式颜色

public class XtepFactory implements AbstractFactory {
    @Override
    public Style getStyle() {
        return new ShortSleeve();
    }
    @Override
    public Color getColor() {
        return new Blue();
    }
}

测试

public static void main(String[] args) {
    AbstractFactory adidas = new AdidasFactory();
    adidas.getStyle().type();
    adidas.getColor().fill();
    
    AbstractFactory xtep = new XtepFactory();
    xtep.getStyle().type();
    xtep.getColor().fill();
}