> For the complete documentation index, see [llms.txt](https://jack80342.gitbook.io/spring-boot/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://jack80342.gitbook.io/spring-boot/iv.-spring-boot-features/43.-testing/43.3-testing-spring-boot-applications/43.3.10-auto-configured-data-jpa-tests.md).

# 43.3.10 自动配置的Data JPA测试

你可以使用`@DataJpaTest`测试JPA应用。它默认配置一个内存型的内嵌数据库，扫描`@Entity`类，并配置Spring Data JPA仓库。其他常规的`@Component` beans不会加载进`ApplicationContext`。

Data JPA测试类是事务型的，默认在每个测试结束时回滚，具体查看Spring参考文档的[相关章节](https://docs.spring.io/spring/docs/5.0.4.RELEASE/spring-framework-reference/testing.html#testcontext-tx-enabling-transactions)。如果这不是你想要的结果，你可以按如下方式对一个测试或是整个类禁用事务管理：

```java
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

@RunWith(SpringRunner.class)
@DataJpaTest
@Transactional(propagation = Propagation.NOT_SUPPORTED)
public class ExampleNonTransactionalTests {

}
```

Data JPA测试类可能会注入一个专为测试设计的[`TestEntityManager`](https://github.com/spring-projects/spring-boot/tree/v2.0.0.RELEASE/spring-boot-project/spring-boot-test-autoconfigure/src/main/java/org/springframework/boot/test/autoconfigure/orm/jpa/TestEntityManager.java)bean以替换标准的JPA `EntityManager`。如果想在`@DataJpaTests`外使用`TestEntityManager`，你可以使用`@AutoConfigureTestEntityManager`注解。如果需要，`JdbcTemplate`也是可用的。下面的例子展示了使用中的`@DataJpaTest`注解：

```java
import org.junit.*;
import org.junit.runner.*;
import org.springframework.boot.test.autoconfigure.orm.jpa.*;

import static org.assertj.core.api.Assertions.*;

@RunWith(SpringRunner.class)
@DataJpaTest
public class ExampleRepositoryTests {

    @Autowired
    private TestEntityManager entityManager;

    @Autowired
    private UserRepository repository;

    @Test
    public void testExample() throws Exception {
        this.entityManager.persist(new User("sboot", "1234"));
        User user = this.repository.findByUsername("sboot");
        assertThat(user.getUsername()).isEqualTo("sboot");
        assertThat(user.getVin()).isEqualTo("1234");
    }

}
```

对于测试来说，内存型的内嵌数据库通常是足够的，因为它们既快又不需要任何安装。如果比较喜欢在真实数据库上运行测试，你可以使用`@AutoConfigureTestDatabase`注解。如下所示：

```java
@RunWith(SpringRunner.class)
@DataJpaTest
@AutoConfigureTestDatabase(replace=Replace.NONE)
public class ExampleRepositoryTests {

    // ...

}
```

在[附录](https://docs.spring.io/spring-boot/docs/2.0.0.RELEASE/reference/htmlsingle/#test-auto-configuration)中可以查看`@DataJpaTest`开启的自动配置列表。