Spring事务的“坑”

最近在项目中发现了个严重的bug，添加事务@Transactional的方法，并没有生效。这样，虽然事务中有for update行级锁，但没有生效，导致数据不一致。
经过调查，如果标记为@Transactional的函数，如果从同一个bean内部调用，则事务不生效。下面是spring官方文档的说明：

Method visibility and @Transactional

When using proxies, you should apply the @Transactional annotation only to methods with public visibility. If you do annotate protected, private or package-visible methods with the @Transactional annotation, no error is raised, but the annotated method does not exhibit the configured transactional settings. Consider the use of AspectJ (see below) if you need to annotate non-public methods.

具体可参考：http://docs.spring.io/spring/docs/3.0.x/spring-framework-reference/html/transaction.html#transaction-declarative-annotations