package designpattern.state;
public class Food {
    private String name;
    private int manufactureDays;// 出厂天数
    private int bestBeforeDays;// 最佳食用天数（从出厂时间算起）
    private int expiryDays;// 保质期天数
    private FoodState foodState;
    public Food(String name, int bestBeforeDays, int expiryDays) {
        this.name = name;
        this.bestBeforeDays = bestBeforeDays;
        this.expiryDays = expiryDays;
        this.foodState = new BestBeforeState();
    }
    public void eat() {
        foodState.reaction(this);
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getManufactureDays() {
        return manufactureDays;
    }
    public void setManufactureDays(int manufactureDays) {
        this.manufactureDays = manufactureDays;
    }
    public int getBestBeforeDays() {
        return bestBeforeDays;
    }
    public void setBestBeforeDays(int bestBeforeDays) {
        this.bestBeforeDays = bestBeforeDays;
    }
    public int getExpiryDays() {
        return expiryDays;
    }
    public void setExpiryDays(int expiryDays) {
        this.expiryDays = expiryDays;
    }
    public FoodState getFoodState() {
        return foodState;
    }
    public void setFoodState(FoodState foodState) {
        this.foodState = foodState;
    }
}

package designpattern.state;
public interface FoodState {
    public void reaction(Food food);
}

package designpattern.state;
public class BestBeforeState implements FoodState {
    @Override
    public void reaction(Food food) {
        if (food.getManufactureDays() <= food.getBestBeforeDays()) {
            System.out.print("第" + food.getManufactureDays() + "天吃，");
            System.out.println("[" + food.getName() + "]在最佳食用期中，好吃~~");
        } else {
            food.setFoodState(new EatableState());
            food.eat();
        }
    }
}

package designpattern.state;
public class EatableState implements FoodState {
    @Override
    public void reaction(Food food) {
        if (food.getManufactureDays() <= food.getExpiryDays()) {
            System.out.print("第" + food.getManufactureDays() + "天吃，");
            System.out.println("[" + food.getName() + "]在可食用期中，味道还可以");
        } else {
            food.setFoodState(new ExpiredState());
            food.eat();
        }
    }
}

package designpattern.state;
public class ExpiredState implements FoodState {
    @Override
    public void reaction(Food food) {
        if (food.getManufactureDays() > food.getExpiryDays()) {
            System.out.print("第" + food.getManufactureDays() + "天吃，");
            System.out.println("[" + food.getName() + "]过期了，没法吃了");
        } else {
            food.setFoodState(new EatableState());
            food.eat();
        }
    }
}

package designpattern.state;
public class Client {
    public static void main(String[] args) {
        Food food = new Food("面包", 1, 7);// 设置最佳食用期1天，保质期7天
        food.setManufactureDays(1);
        food.eat();
        food.setManufactureDays(3);
        food.eat();
        food.setManufactureDays(10);
        food.eat();
    }
}

第1天吃，[面包]在最佳食用期中，好吃~~
第3天吃，[面包]在可食用期中，味道还可以
第10天吃，[面包]过期了，没法吃了