Java 当涉及继承时，如何在Hibernate/JPA中指定列名？

我想我是想在这里吃我的蛋糕，但我们会看看是否有一个可行的解决方案来解决我所寻找的问题。我有一个springboot/JPA/Hibernate应用程序，它将与MySQL对话，作为它的后台存储。从OOP的角度来看，我有几种情况下我的实体类形成了一个父/子层次结构，如下所示：

// Groovy pseudo-code!
class Vehicle {
  Long id
  Long maxSpeed
  String make
  String model
}

class Motorcycle extends Vehicle {
  Boolean isTwoStroke
}

class Car extends Vehicle {
  Boolean hasLeatherInterior
}

等等。通常，在JPA之外，我可能会这样设计他们各自的表格：

CREATE TABLE motorcycles (
  motorcycle_id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  motorcycle_max_speed BIGINT UNSIGNED,
  motorcycle_make VARCHAR(50) NOT NULL,
  motorcycle_model VARCHAR(50) NOT NULL,
  motorcycle_is_two_speed BIT NOT NULL,

  # PK, FK, UC, index constraints down here (omitted for brevity)
);

CREATE TABLE cars (
  car_id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  car_max_speed BIGINT UNSIGNED,
  car_make VARCHAR(50) NOT NULL,
  car_model VARCHAR(50) NOT NULL,
  car_has_leather_interior BIT NOT NULL,

  # PK, FK, UC, index constraints down here (omitted for brevity)
);

CREATE TABLE motorcycles (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  max_speed BIGINT UNSIGNED,
  make VARCHAR(50) NOT NULL,
  model VARCHAR(50) NOT NULL,
  motorcycle_is_two_speed BIT NOT NULL,

  # PK, FK, UC, index constraints down here (omitted for brevity)
);

CREATE TABLE cars (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  max_speed BIGINT UNSIGNED,
  make VARCHAR(50) NOT NULL,
  model VARCHAR(50) NOT NULL,
  car_has_leather_interior BIT NOT NULL,

  # PK, FK, UC, index constraints down here (omitted for brevity)
);

理想情况下我希望保持此表的设计不变，“父车辆”列的名称与上面的名称完全相同。但是如果我正确地理解了Hibernate/JPAAPI，那么我认为如果不做出某种牺牲，这是不可能的。我想我要么需要牺牲应用层的继承性，这样子类中的列就可以完全按照DB中的列命名：

@Entity
class Motorcycle {    // No longer extends Vehicle :-(
  @Id
  @GeneratedValue(strategy=GenerationType.IDENTITY)
  @Column(name = "motorcycle_id")
  Long id

  @Column(name = "motorcycle_max_speed")
  Long maxSpeed

  @Column(name = "motorcycle_make")
  String make

  @Column(name = "motorcycle_model")
  String model

  @Column(name = "motorcycle_is_two_speed")
  Boolean isTwoStroke
}

@Entity
class Car {    // No longer extends Vehicle :-(
  @Id
  @GeneratedValue(strategy=GenerationType.IDENTITY)
  @Column(name = "car_id")
  Long id

  @Column(name = "car_max_speed")
  Long maxSpeed

  @Column(name = "car_make")
  String make

  @Column(name = "car_model")
  String model

  @Column(name = "car_has_leather_interior")
  Boolean hasLeatherInterior
}

或我认为我可以保留应用层继承，但随后需要像这样重构我的DB表：

CREATE TABLE motorcycles (
  motorcycle_id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  motorcycle_max_speed BIGINT UNSIGNED,
  motorcycle_make VARCHAR(50) NOT NULL,
  motorcycle_model VARCHAR(50) NOT NULL,
  motorcycle_is_two_speed BIT NOT NULL,

  # PK, FK, UC, index constraints down here (omitted for brevity)
);

CREATE TABLE cars (
  car_id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  car_max_speed BIGINT UNSIGNED,
  car_make VARCHAR(50) NOT NULL,
  car_model VARCHAR(50) NOT NULL,
  car_has_leather_interior BIT NOT NULL,

  # PK, FK, UC, index constraints down here (omitted for brevity)
);

CREATE TABLE motorcycles (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  max_speed BIGINT UNSIGNED,
  make VARCHAR(50) NOT NULL,
  model VARCHAR(50) NOT NULL,
  motorcycle_is_two_speed BIT NOT NULL,

  # PK, FK, UC, index constraints down here (omitted for brevity)
);

CREATE TABLE cars (
  id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
  max_speed BIGINT UNSIGNED,
  make VARCHAR(50) NOT NULL,
  model VARCHAR(50) NOT NULL,
  car_has_leather_interior BIT NOT NULL,

  # PK, FK, UC, index constraints down here (omitted for brevity)
);

---

所以我问：我是否可以保留我的应用层继承（并让摩托车和汽车继承车辆的属性）和使用我的首选约定命名DB表列（

指定一个类，其映射信息应用于从该类继承的实体。映射的超类
没有为其定义单独的表。

） 车辆类别：

@MappedSuperclass
public class Vehicle {
    @Id
    @GeneratedValue
    Long id;
    Long maxSpeed;
    String make;
    String model;
}

摩托车亚类

 @Entity
    @AttributeOverrides({
            @AttributeOverride(name = "id", column = @Column(name = "motorcycle_id"))
    })
    public class Motorcycle extends Vehicle {
        Boolean isTwoStroke;
    }

---

谢谢@Bhushan Uniyal（+1）-如果您不介意的话，请回答以下问题：我计划先创建自己的数据库，然后使用

hibernate.hbm2ddl.auto=validate

（而不是

create

或其他方法）。我还计划将MySQL中的主键设置为

AUTO_INCREMENT

列。如果MySQL PKs已经自动递增，并且如果我让Hibernate简单地

validate

验证我现有的数据库，我甚至需要在代码中的PK字段上指定

@GeneratedValue

？再次感谢！@smeeb yes您可以删除@Generated值，它将在没有它的情况下工作，因为您正在数据库级别使用

AUTO_INCREMEN

启用。另外

hibernate.hbm2ddl.AUTO=validate

将处理您的数据库架构，因此这里没有问题