EntityManager refresh

Question

I have web application using JPA. This entity manager keeps bunch of entites and suddenly I update the database from other side. I use MySQL and I use

Answer 1

entityManager.getEntityManagerFactory().getCache().evictAll()

Refresh is something different since it modifies your object. This line will just empty the cache, so if you fetch objects changed outside the entity manager, it will do an actual database query instead of using the outdated cached value.