java - 如果数据库 ID 不再存在，如何忽略删除时的异常？

Question

我想忽略在 spring CrudRepository 中的删除操作期间发生的任何异常。

@Tranactional
public void remove(Long id) {
    try {
        if (id != null) dao.delete(id); //CrudRepository
    } catch (Exception e) {
        //ignore any exceptions, it's not critical delete
    }
}

问题:当我运行它时，我仍然收到以下异常(例如，如果要删除的 ID 在数据库中不再存在 - 意味着它可能已被同时删除)。我怎么能忽略它呢？

org.springframework.transaction.TransactionSystemException: Could not commit JPA transaction; nested exception is javax.persistence.RollbackException: Transaction marked as rollbackOnly
    at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:526) ~[spring-orm-4.2.6.RELEASE.jar:4.2.6.RELEASE]
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:761) ~[spring-tx-4.2.6.RELEASE.jar:4.2.6.RELEASE]
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:730) ~[spring-tx-4.2.6.RELEASE.jar:4.2.6.RELEASE]
    at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:485) ~[spring-tx-4.2.6.RELEASE.jar:4.2.6.RELEASE]
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:291) ~[spring-tx-4.2.6.RELEASE.jar:4.2.6.RELEASE]
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) ~[spring-tx-4.2.6.RELEASE.jar:4.2.6.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.2.6.RELEASE.jar:4.2.6.RELEASE]
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:655) ~[spring-aop-4.2.6.RELEASE.jar:4.2.6.RELEASE]

Answer 1

即使您捕获了异常，事务管理器也会将事务标记为只回滚，因此当您在方法结束时提交时，您将遇到一个 TransactionSystemException 异常。

第一个 react 是标记方法 @Transactional(noRollbackFor=EmptyResultDataAccessException.class) 但这并不能解决问题，因为如果你看一下 SimpleJpaRepository 类将看到 delete 方法被标记为 transactional，因此当抛出异常时，此 @Transactional 将您的事务标记为仅回滚。

在我看来，解决方案是调用 findOne 方法，然后如果实体存在则调用 delete 方法(按实体而不是按 ID 调用 delete 方法):

@Tranactional
public void remove(Long id) {
    if (id != null) {
     YouEntity entity= dao.findOne(id);
     if (nonNull(entity)) {
        dao.delete(entity);
     }
    }
 }