persistence4j is a small and lightweight Java object persister that uses JDBC to persist data into a relational database. The library frees you from writing the Data transfer objects - just create a POJO and simply save it. Transactional and non-transactional connections are supported and can be configured from the simple properties file.
The Generic Repository (grepo) is a framework for Java which allows you to access (database) repositories in a generic and consistent manner. Using grepo, it is generally no longer required to provide all the boilerplate code which is necessary in order to access (database) repositories from Java. All you have to do is write appropriate database code (queries, procedures, functions, etc.), an appropriately annotated Java interface, and very little Spring configuration.