Transaction Internals

The CGLIB proxy intercepts the call, TransactionInterceptor reads the annotation attributes, PlatformTransactionManager acquires a connection and binds it to the thread, the method runs on that connection, and on return the manager commits or rolls back.

PlatformTransactionManager is the interface for begin/commit/rollback, and TransactionSynchronizationManager uses ThreadLocal to bind the connection to the current thread so all repository calls share one connection per transaction.