Theoretical part: What are advantages of using immutable objects? HashCode vs equals contract. What is final, finally, finalize? What is the difference between ArrayList & LinkedList? What is the difference between HashSet & LinkedHashSet & TreeSet? DRY, SOLID? What are SQL isolation levels? Which columns should we choose when working with index? How SQL indexing works? SQL index vs select speed of execution. SQL Having keyword? Describe your experience working with Stream API. What is the difference between .map() & .flatMap()? What are atomic operations? What is race condition? Given 3 Beans which has a parent class Car: ToyotaCar, MersCar, AudiCar. During initialization of one of Car classes, what system will return? How ManyToMany relationship works? Give examples. What is Spring Framework & its applications? What annotations are used in Spring MVC? What is Hibernate? What is security filter chain? What is Autoconfiguration? Practical part: Create CRUD app with books & authors, filter information.