数据库使用数据Mysql 超市购物商品信息和购买信息表：goods 和 order 完成对顾客下单业务； Order表：主键、日期、经办人、金额、折扣、支付金额 Goods表：主键、商品代码、商品名称、进价、售价、数量 使用ssm框架编写此代码

首先，需要在Mysql中创建两张表，goods和order，具体的SQL语句如下：

CREATE TABLE `goods` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `code` varchar(50) NOT NULL,
  `name` varchar(50) NOT NULL,
  `purchase_price` double NOT NULL,
  `sale_price` double NOT NULL,
  `quantity` int(11) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

CREATE TABLE `order` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `date` date NOT NULL,
  `handler` varchar(50) NOT NULL,
  `amount` double NOT NULL,
  `discount` double NOT NULL,
  `pay_amount` double NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

接下来，使用SSM框架进行开发。首先需要创建对应的实体类Goods和Order，具体代码如下：

Goods.java

public class Goods {
    private int id;
    private String code;
    private String name;
    private double purchasePrice;
    private double salePrice;
    private int quantity;

    // 省略getter和setter方法
}

Order.java

public class Order {
    private int id;
    private Date date;
    private String handler;
    private double amount;
    private double discount;
    private double payAmount;

    // 省略getter和setter方法
}

接下来，创建对应的DAO接口和Mapper文件。具体代码如下：

GoodsMapper.java

public interface GoodsMapper {
    void insertGoods(Goods goods);
    void updateGoods(Goods goods);
    void deleteGoods(int id);
    List<Goods> selectAllGoods();
    Goods selectGoodsById(int id);
}

GoodsMapper.xml

<mapper namespace="com.example.mapper.GoodsMapper">
    <insert id="insertGoods" parameterType="com.example.entity.Goods">
        INSERT INTO goods(code, name, purchase_price, sale_price, quantity)
        VALUES(#{code}, #{name}, #{purchasePrice}, #{salePrice}, #{quantity})
    </insert>

    <update id="updateGoods" parameterType="com.example.entity.Goods">
        UPDATE goods
        SET code=#{code}, name=#{name}, purchase_price=#{purchasePrice}, sale_price=#{salePrice}, quantity=#{quantity}
        WHERE id=#{id}
    </update>

    <delete id="deleteGoods" parameterType="int">
        DELETE FROM goods
        WHERE id=#{id}
    </delete>

    <select id="selectAllGoods" resultType="com.example.entity.Goods">
        SELECT * FROM goods
    </select>

    <select id="selectGoodsById" parameterType="int" resultType="com.example.entity.Goods">
        SELECT * FROM goods
        WHERE id=#{id}
    </select>
</mapper>

OrderMapper.java

public interface OrderMapper {
    void insertOrder(Order order);
    void updateOrder(Order order);
    void deleteOrder(int id);
    List<Order> selectAllOrders();
    Order selectOrderById(int id);
}

OrderMapper.xml

<mapper namespace="com.example.mapper.OrderMapper">
    <insert id="insertOrder" parameterType="com.example.entity.Order">
        INSERT INTO order(date, handler, amount, discount, pay_amount)
        VALUES(#{date}, #{handler}, #{amount}, #{discount}, #{payAmount})
    </insert>

    <update id="updateOrder" parameterType="com.example.entity.Order">
        UPDATE order
        SET date=#{date}, handler=#{handler}, amount=#{amount}, discount=#{discount}, pay_amount=#{payAmount}
        WHERE id=#{id}
    </update>

    <delete id="deleteOrder" parameterType="int">
        DELETE FROM order
        WHERE id=#{id}
    </delete>

    <select id="selectAllOrders" resultType="com.example.entity.Order">
        SELECT * FROM order
    </select>

    <select id="selectOrderById" parameterType="int" resultType="com.example.entity.Order">
        SELECT * FROM order
        WHERE id=#{id}
    </select>
</mapper>

最后，创建对应的Service接口和实现类。具体代码如下：

GoodsService.java

public interface GoodsService {
    void insertGoods(Goods goods);
    void updateGoods(Goods goods);
    void deleteGoods(int id);
    List<Goods> selectAllGoods();
    Goods selectGoodsById(int id);
}

GoodsServiceImpl.java

@Service
public class GoodsServiceImpl implements GoodsService {
    @Autowired
    private GoodsMapper goodsMapper;

    @Override
    public void insertGoods(Goods goods) {
        goodsMapper.insertGoods(goods);
    }

    @Override
    public void updateGoods(Goods goods) {
        goodsMapper.updateGoods(goods);
    }

    @Override
    public void deleteGoods(int id) {
        goodsMapper.deleteGoods(id);
    }

    @Override
    public List<Goods> selectAllGoods() {
        return goodsMapper.selectAllGoods();
    }

    @Override
    public Goods selectGoodsById(int id) {
        return goodsMapper.selectGoodsById(id);
    }
}

OrderService.java

public interface OrderService {
    void insertOrder(Order order);
    void updateOrder(Order order);
    void deleteOrder(int id);
    List<Order> selectAllOrders();
    Order selectOrderById(int id);
}

OrderServiceImpl.java

@Service
public class OrderServiceImpl implements OrderService {
    @Autowired
    private OrderMapper orderMapper;

    @Override
    public void insertOrder(Order order) {
        orderMapper.insertOrder(order);
    }

    @Override
    public void updateOrder(Order order) {
        orderMapper.updateOrder(order);
    }

    @Override
    public void deleteOrder(int id) {
        orderMapper.deleteOrder(id);
    }

    @Override
    public List<Order> selectAllOrders() {
        return orderMapper.selectAllOrders();
    }

    @Override
    public Order selectOrderById(int id) {
        return orderMapper.selectOrderById(id);
    }
}

最后，在Controller中调用Service中的方法即可完成对顾客下单业务。具体代码如下：

@RestController
@RequestMapping("/order")
public class OrderController {
    @Autowired
    private OrderService orderService;

    @PostMapping("/add")
    public String addOrder(@RequestBody Order order) {
        orderService.insertOrder(order);
        return "添加成功";
    }

    @DeleteMapping("/delete/{id}")
    public String deleteOrder(@PathVariable("id") int id) {
        orderService.deleteOrder(id);
        return "删除成功";
    }

    @PutMapping("/update")
    public String updateOrder(@RequestBody Order order) {
        orderService.updateOrder(order);
        return "修改成功";
    }

    @GetMapping("/list")
    public List<Order> listOrder() {
        return orderService.selectAllOrders();
    }

    @GetMapping("/get/{id}")
    public Order getOrderById(@PathVariable("id") int id) {
        return orderService.selectOrderById(id);
    }
}

这样，就完成了对顾客下单业务的开发。