Category Archives: Q&A

Question and answer collection

Java Basic

1. What is Class, Object, State, Behavior? Class: A template that describes the kinds of state and behavior that objects of its type support Object: At runtime, when the Java Virtual Machine (JVM) encounters the new keyword, it will use the appropriate class to make an object which is an instance of that class. That… Read More »

Category: Q&A

Java, OOP questions

Question 01: What are the characteristics of Object-Oriented programming language? Encapsulation – Encapsulation is capturing data and keeping it safely and securely from outside interfaces. Inheritance- This is the process by which a class can be derived from a base class with all features of the base class and some of its own. This increases… Read More »

Category: Q&A

Database, JPA-Hibernate, Spring technical questions

Question 01. Why can’t I use ResultSet object after the JDBC transaction completed? Because ResultSet is a lazy cache of data from the database and can have only a few rows from the database [Ref JDBC] Question 02: What are advantages of ORM Productivity, because of automation Maintainability, raising the level of abstraction via use of mappings. Performance, by… Read More »