拋出例外和事務回滾后更新物體欄位值

我開發了一個測驗專案來重現這個問題。

這是一個專案結構：

pom.xml 檔案：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.1</version>
        <relativePath/>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>value-updated-after-fail-spring</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>17</maven.compiler.source>
        <maven.compiler.target>17</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
    </dependencies>

</project>

Persone.java 檔案：

@Entity
@NoArgsConstructor(access = AccessLevel.PROTECTED)
@RequiredArgsConstructor
@AllArgsConstructor
@Builder
@Getter
@Setter
@ToString
@FieldDefaults(level = AccessLevel.PRIVATE)
public class Person {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    Long id;

    @Column(nullable = false)
    @NonNull
    String name;
}

PersonRepository.java 檔案：

@Repository
public interface PersonRepository extends JpaRepository<Person, Long> {}

PersonService.java 檔案：

@Component
public class PersonService {

    private final PersonRepository repository;

    public PersonService(PersonRepository repository) {
        this.repository = repository;
    }

    @Transactional
    public Person create(String name) {
        return repository.save(new Person(name));
    }

    @Transactional
    public Person save(Person person) {
        if(StringUtils.isBlank(person.getName())) {
            throw new RuntimeException();
        }
        Person personFromDB = getById(person.getId());
        personFromDB.setName(person.getName());
        return repository.save(personFromDB);
    }

    @Transactional
    public Person getById(Long id) {
        return repository.findById(id)
                .orElseThrow(NullPointerException::new);
    }

    @Transactional
    public void deleteAll() {
        repository.deleteAll();
    }
}

application.properties 檔案：

spring.datasource.url=jdbc:h2:mem:test;DB_CLOSE_DELAY=-1
spring.datasource.username=sa
spring.datasource.password=
spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.show-sql=true
spring.h2.console.enabled=true
spring.datasource.driver-class-name=org.h2.Driver
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect

TestApplicationConfiguration.java 檔案

@SpringBootConfiguration
@EnableAutoConfiguration
@EnableJpaRepositories
@EntityScan("net.example.model")
@ComponentScan(basePackages = "net.example")
public class TestApplicationConfiguration {}

PersonServiceTest.java 檔案：

@DataJpaTest
@AutoConfigureTestDatabase(replace = Replace.NONE)
class PersonServiceTest {

    @Autowired
    private PersonService service;

    @AfterEach
    void tearDownEach() {
        service.deleteAll();
    }

    @Test
    void rename() {
        String expected = "name";
        Person person = service.create(expected);
        Person personFromDB = service.getById(person.getId());
        personFromDB.setName("");
        assertThrows(RuntimeException.class, () -> service.save(personFromDB));
        assertEquals(expected, service.getById(personFromDB.getId()).getName());
    }
}

問題：最后一個斷言失敗

org.opentest4j.AssertionFailedError:
Expected :name
Actual   :

我已經嘗試解決這個問題了嗎？

1. 我試圖洗掉@TransactionalPersonService#getById 方法的注釋以避免從快取中獲取物體。- 這并沒有解決問題
2. 我試圖添加spring.cache.type=none到application.properties檔案以禁用快取。- 這并沒有解決問題

為什么我認為它是快取？

當我對此進行除錯時，我發現該PersonService#getById()方法沒有回傳實際資料，但該方法回傳了一個標題已更改的快取物件。呼叫該PersonService#save方法后資料庫未更改，因為它引發了例外

也許我沒有正確開發測驗。也許我應該改變保存更改資料的方法。

請分享最佳實踐和文章，以更好地了解如何更新資料以及如何正確配置和撰寫 Spring Boot 應用程式的測驗。

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