spring aop如何使用jdk代理处理@Transactional？

Question

If one Service class has method with @Transactional, then spring will use proxy to handle it. But if one Transactional method call another one

@Transactional
public FeedBackModel getOne() {
    ///..
    return getTwo();
}
@Transactional
public FeedBackModel getTwo() {
    return null;
}

like this.

if it is jdk proxy, then second @Transactional will not work. But spring PROPAGATION will handle this correctly. How it works?

Answer 1

If you are trying to commit a transaction in getTwo() which is called from getOne() , that will not work, not even when both are @Transactional. Refer to the documentation :

...please do take the Spring team's advice and only annotate concrete classes (and the methods of concrete classes) with the @Transactional annotation.

Note: Since this mechanism is based on proxies, only 'external' method calls coming in through the proxy will be intercepted. This means that 'self-invocation' , ie a method within the target object calling some other method of the target object, won't lead to an actual transaction at runtime even if the invoked method is marked with @Transactional!