Spring application has Cglib2AopProxy warnings

Maybe you have extended JdbcDaoSupport and added @Transactional annotations.

You can set the Cglib2AopProxy logger to log level ERROR to avoid the warn messages. For example if using log4j and log4j.properties:

log.logger.org.springframework.aop.framework.Cglib2AopProxy = ERROR

This is most likely caused by the @Transactional annotation, Spring wraps your DAO in a proxy to add the transactional behavior.

I would recommend to make your DAO implement an Interface (create and use an interface for your DAO), this will allow Spring to use a JDK dynamic proxy instead of having to use CGLib.

Using CGLIB has a limitation that methods marked as final in target class can’t be advised as final methods can’t be overridden (CGLIB creates a subclass of target class at runtime) but this limitation disappears in case of using JDK dynamic proxies.

Reference