Some problems and its solutions

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 hibernate 2 cur cache memory var: L1(Level bir) burada entitymanager a aiddir. bazadan gelen entityler cacheda saxlanir ve her entitymanagere xasdir L2(level 2) burada ise umumiyyetle EntityManagerFactory ye xidmet eden entiymanagerler arasinda shared cache memorydir ve level 1 den daha uzun muddetlidir level 2 cache i aktivleshdirmek uchun dependency elave edilir projecte ve 1-2 config edilir Javada 4 cur reference type var : https://dzone.com/articles/reference-types-java-part-1 Strong references. Soft references. Weak references. Phantom references entitymanager de weak referance var , ve o strongla muqayisede GC terefinden istenilen an siline biler ram lazim olsa. soft referance - strongdan zeif , weakdan gucludur ve GC onu ancaq en vacib hallarda sile biler, weak i her memory chatmiyanda sile biler ama softu ancaq outofmemory alacagi teqdirde silib ishlede biler ve soft un omru uzun olur . ve Level 2 cache da istifade edir bunu hibernate. burda da bele shey varki , LRU(last r...

With using this approach we can get any of field of entity and this way is more efficient rather than get all entity fileds , example in below: @Repository public interface CompanyRepo extends JpaRepository<Company, Long> {     Integer countById(long id);     <T extends CompanyViewProtocol> Optional<T> findById(long id, Class<T> type); } public interface CompanyViewProtocol { } public interface ContactDetailView extends CompanyViewProtocol {     CompanyContactDetail getContactDetail(); } in there companyRepo.findById(1L,ContactDetailView.class)   gives us CompanyContactDetail