java工厂模式用面向象思想解决饭店会员消费问题，酒店会员分为三个等级：钻石会员，黄金 会员，白银会员。钻石会员享受用餐5折待遇，黄金会员享受7折待遇，白银会员 享受9折待遇，饭店会用一种核算消费的方法计算三种会员的消费

首先，我们需要定义一个会员类，包含会员等级和消费金额两个属性：

public class Member {
    private String level; // 会员等级
    private double consumption; // 消费金额

    public Member(String level, double consumption) {
        this.level = level;
        this.consumption = consumption;
    }

    public String getLevel() {
        return level;
    }

    public void setLevel(String level) {
        this.level = level;
    }

    public double getConsumption() {
        return consumption;
    }

    public void setConsumption(double consumption) {
        this.consumption = consumption;
    }
}

接下来，我们需要定义一个工厂类，根据会员等级来创建对应的会员对象，并计算消费金额：

public class MemberFactory {
    public static Member createMember(String level, double consumption) {
        Member member = null;
        switch (level) {
            case "钻石会员":
                member = new DiamondMember(consumption);
                break;
            case "黄金会员":
                member = new GoldMember(consumption);
                break;
            case "白银会员":
                member = new SilverMember(consumption);
                break;
            default:
                break;
        }
        return member;
    }
}

然后，我们需要定义三个具体的会员类，分别对应三个不同的会员等级：

public class DiamondMember extends Member {
    public DiamondMember(double consumption) {
        super("钻石会员", consumption);
    }

    @Override
    public double getConsumption() {
        return super.getConsumption() * 0.5;
    }
}

public class GoldMember extends Member {
    public GoldMember(double consumption) {
        super("黄金会员", consumption);
    }

    @Override
    public double getConsumption() {
        return super.getConsumption() * 0.7;
    }
}

public class SilverMember extends Member {
    public SilverMember(double consumption) {
        super("白银会员", consumption);
    }

    @Override
    public double getConsumption() {
        return super.getConsumption() * 0.9;
    }
}

最后，我们可以使用工厂类创建不同等级的会员对象，并根据消费金额进行计算：

public class Main {
    public static void main(String[] args) {
        Member diamondMember = MemberFactory.createMember("钻石会员", 1000);
        System.out.println("钻石会员消费：" + diamondMember.getConsumption());

        Member goldMember = MemberFactory.createMember("黄金会员", 1000);
        System.out.println("黄金会员消费：" + goldMember.getConsumption());

        Member silverMember = MemberFactory.createMember("白银会员", 1000);
        System.out.println("白银会员消费：" + silverMember.getConsumption());
    }
}

输出结果为：

钻石会员消费：500.0
黄金会员消费：700.0
白银会员消费：900.0

以上就是使用面向对象思想解决饭店会员消费问题的工厂模式实现。