工厂模式例子

interface Fruit{
    public void eat();
}

class Apple implements Fruit{
    @Override
    public void eat() {
        System.out.println("吃苹果");
    }
}
class Cherry implements Fruit{
    @Override
    public void eat() {
        System.out.println("吃樱桃");
    }
}

class Factory{ //工厂
    public static Fruit getInstance(String className){
        if ("apple".equals(className)){
            return new Apple();
        }else if ("cherry".equals(className)){
            return new Cherry();
        }else{
            return null;
        }
    }
}

public class FactoryDemo {
    public static void main(String[] args){
        Fruit f = Factory.getInstance(args[0]);
        f.eat();
    }
}