Java Spring数据存储库JPA实体继承问题：无法实例化抽象类或接口

我正在使用下面的web应用程序堆栈，当我运行TestNG测试并初始化容器时，我的测试类无法自动连接ExampleRepository，出现以下异常。有没有关于如何描绘这种关系的想法？当我用同一个web应用程序启动jetty web服务器时，我没有收到任何启动异常，因此AbstractTransactionalTestNGSpringContextTests可能会出现问题

堆栈：

    Spring - 3.2.2.RELEASE
    Spring Data - 1.3.0.RELEASE
    Hibernate - 3.6.10.Final
    TestNG - 6.1.1

Cannot instantiate abstract class or interface: com.test.Example; nested exception is org.hibernate.InstantiationException

@Entity
@Table(name = "EXAMPLE")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "type", discriminatorType = DiscriminatorType.STRING)
public abstract class Example {}


@Entity
@DiscriminatorValue("examplea")
public class ExampleA extends Example {}

@Entity
@DiscriminatorValue("exampleb")
public class ExampleB extends Example {}

public interface ExampleRepository extends JpaRepository<Example, Long> {}

public class ExampleTest extends AbstractTransactionalTestNGSpringContextTests{
      @Autowired
      private ExampleRepository exampleRepository;
}

例外情况：

    Spring - 3.2.2.RELEASE
    Spring Data - 1.3.0.RELEASE
    Hibernate - 3.6.10.Final
    TestNG - 6.1.1

Cannot instantiate abstract class or interface: com.test.Example; nested exception is org.hibernate.InstantiationException

@Entity
@Table(name = "EXAMPLE")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "type", discriminatorType = DiscriminatorType.STRING)
public abstract class Example {}


@Entity
@DiscriminatorValue("examplea")
public class ExampleA extends Example {}

@Entity
@DiscriminatorValue("exampleb")
public class ExampleB extends Example {}

public interface ExampleRepository extends JpaRepository<Example, Long> {}

public class ExampleTest extends AbstractTransactionalTestNGSpringContextTests{
      @Autowired
      private ExampleRepository exampleRepository;
}

JPA实体：

    Spring - 3.2.2.RELEASE
    Spring Data - 1.3.0.RELEASE
    Hibernate - 3.6.10.Final
    TestNG - 6.1.1

Cannot instantiate abstract class or interface: com.test.Example; nested exception is org.hibernate.InstantiationException

@Entity
@Table(name = "EXAMPLE")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "type", discriminatorType = DiscriminatorType.STRING)
public abstract class Example {}


@Entity
@DiscriminatorValue("examplea")
public class ExampleA extends Example {}

@Entity
@DiscriminatorValue("exampleb")
public class ExampleB extends Example {}

public interface ExampleRepository extends JpaRepository<Example, Long> {}

public class ExampleTest extends AbstractTransactionalTestNGSpringContextTests{
      @Autowired
      private ExampleRepository exampleRepository;
}

存储库：

    Spring - 3.2.2.RELEASE
    Spring Data - 1.3.0.RELEASE
    Hibernate - 3.6.10.Final
    TestNG - 6.1.1

Cannot instantiate abstract class or interface: com.test.Example; nested exception is org.hibernate.InstantiationException

@Entity
@Table(name = "EXAMPLE")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "type", discriminatorType = DiscriminatorType.STRING)
public abstract class Example {}


@Entity
@DiscriminatorValue("examplea")
public class ExampleA extends Example {}

@Entity
@DiscriminatorValue("exampleb")
public class ExampleB extends Example {}

public interface ExampleRepository extends JpaRepository<Example, Long> {}

public class ExampleTest extends AbstractTransactionalTestNGSpringContextTests{
      @Autowired
      private ExampleRepository exampleRepository;
}

---

将示例类作为接口，并让其他类实现它。 正如异常明确指出的，您不能实例化抽象类。

---

将Example类作为接口，您可以实例化它的类型，即实现它的类。

Example是一个抽象类，因为它还有ExampleA和ExampleBThat类使用的实现代码，但您无法自动关联它的类型。您可以让您的类实现另一个接口，并扩展这个类，然后尝试自动连接接口类型。我想我理解您的意思。让示例成为一个具体的非抽象类，只创建一个ExampleA和ExampleB可以实现的接口。我将使用特定的repos

ExampleArespository

和

ExampleBrespository