java - Spring事务感知缓存不起作用

Question

我正在使用 Spring 缓存抽象，使用 Ehcache 作为缓存提供程序。我正在尝试将缓存操作附加到 Spring JPA 事务，但无法这样做。

即使事务失败/回滚缓存也会发生。

配置，

        @Bean
    public EhCacheManagerFactoryBean cacheManagerUsingSpringApi() {
        EhCacheManagerFactoryBean ehCacheManagerFactoryBean = new EhCacheManagerFactoryBean();

        // provide xml file for ehcache configuration/
        ehCacheManagerFactoryBean.setConfigLocation(new ClassPathResource("spring-cache-abs-ehcache.xml"));

        return ehCacheManagerFactoryBean;
    }

    @Bean
    public org.springframework.cache.CacheManager ehCacheCacheManager() {
        final EhCacheCacheManager ehCacheCacheManager = new EhCacheCacheManager(cacheManagerUsingSpringApi().getObject());
        ehCacheCacheManager.setTransactionAware(true); // Setting  transaction aware
        return ehCacheCacheManager;
    }

spring-cache-abs-ehcache.xml，

    <ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="ehcache.xsd"
         updateCheck="true"
         monitoring="autodetect"
         dynamicConfig="true">

    <cache name="EmployeeCache"
           maxEntriesLocalHeap="10000"
           eternal="false"
           timeToIdleSeconds="300" timeToLiveSeconds="600"
           memoryStoreEvictionPolicy="LFU"
           transactionalMode="off">
        <persistence strategy="localTempSwap" />
    </cache>
</ehcache>

员工存储库，

    public interface EmployeeRepository extends JpaRepository<Employee, Long>, CustomEmployeeRepository {
    }

交易方法，

    @Repository
public class EmployeeRepositoryImpl implements CustomEmployeeRepository {

    @PersistenceContext
    private EntityManager entityManager;

    @Autowired
    private CacheManager cacheManager;

    // THIS METHOD SHOULD NOT PUT INTO CACHE WITH NEW NAME
    @Override
    @Transactional
    @Cacheable(cacheNames = "EmployeeCache", key = "#a0.id")
    public Employee customUpdate(Employee employee) {
        employee.setFirstName(UUID.randomUUID().toString());
        entityManager.merge(employee);

        // rolling back transaction 
        TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();

        return employee;
    }
}

测试用例(调用者)，

    @Test
public void testCustomUpdate() {
    // GIVEN
    Employee employee = new Employee();
    employee.setFirstName(UUID.randomUUID().toString());
    employee.setLastName(UUID.randomUUID().toString());
    final Employee savedEmployee = employeeRepository.save(employee);

    // WHEN
    final Employee updatedEmployee = employeeRepository.customUpdate(savedEmployee);

    // THEN
    final Cache employeeCache = cacheManager.getCache("EmployeeCache");
    final Cache.ValueWrapper object = employeeCache.get(updatedEmployee.getId());
    assertNull(object);
}

测试应该成功，即如果事务在该方法中回滚，则 spring 不应将数据放入方法 employeeRepository.customUpdate 中的缓存中。但是，即使事务失败，Spring 也会将数据放入缓存中。注意:奇怪的是，如果缓存中已经存在条目，那么如果事务失败，@CachePut 不会更新缓存中的条目。

因此，如果我用 @CachePut(cacheNames = "EmployeeCache", key = "#result.id") 注释 employeeRepository.save ，则缓存不会更新更新通话。

这里缺少什么？

Answer 1

选项 1:使用建议排序，

引用: https://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#aop-ordering

以下声明将导致首先执行事务性建议，然后执行可缓存建议。

<tx:annotation-driven order="0"/>

<cache:annotation-driven cache-manager="ehCacheManager" order="1"/>

选项2:在不同的方法上注解@Cacheable和@Transactional

如果您从另一个使用 @Transactional 注释的方法调用 @Cacheable 注释的方法，您将看到代码正在运行。除非您实现了建议排序，否则同一方法上的两个注释(即 @Cacheable 和 @Transaction)不会对您的事业有帮助。请参阅下面您的逻辑的粗略实现。

    @Override
    @Transactional
    public Employee customUpdate(Employee employee) {
        Employee mergedEmployee = updateHelper(employee);

        // rolling back transaction 
        TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();

        return mergedEmployee;
    }

    @Cacheable(cacheNames = "EmployeeCache", key = "#a0.id")
    public Employee updateHelper(Employee employee)) {
        employee.setFirstName(UUID.randomUUID().toString());
        //On a merge(...) call on the entityManager, the returned item is the managed 
        //instance
        return entityManager.merge(employee); 
    }