Hashmap key problems, most usuals -> reference of a key that is an Object and it change its value inside Entity rules to create a table, need ID @entity annotation Spring Transactional types for db What annotation you use and hoy do you inject via - Contructor, variable, set, what is the best way? -> Contructor, why Spring annotations in general, Diference with Service & Repository annotation,-> mostly excpetions String pool? what is Rest, what is , difierence between POST & PUT Patterns, say some and explain them Solid, best priciple, what do you like and why Have you coded TDD way? how do you test, what kind of test , Capture in mockito what is Multithreading, deadlock, how it is generated, -> synchronized methods or code, and block Hibernate questions, native queries?, some annotations. Example of 2 interfaces extended in a class, you call same method, what happen?,-> it breaks Stream questions Best practices questions, code review what do you check try/catch/final, -> (if system.exit() in catch final is not executed.) try with resources, kafka examplain what is your exaperience with it: diference Topic and Queue How to manage a big amount of exceptions in Spring controllers, -> @ControllerAdvice What was your experience in RDB, manual queries , in project repositories. How do you do inmutable objects? -> final *There were more questions but I could not remember all of them*