15 Must Know Java Interview Questions After 2 Years of Experience

Interview Questions that every developer should have the answer

Enterprise Java Application development is growing every day and new features being introduced but the the beginners have always start from the basics. The questions listed below are what in general a Java developer should be able to answer after 2 years of experience. (Assuming no prior exposure to Java)

Core Java

1) What is the purpose of serialization?

2) What is the difference between JDK and JRE?

3) What is the difference between equals and ==?

4) When will you use Comparator and Comparable interfaces?

5) What is the wait/notify mechanism?

6) What is the difference between checked and unchecked exceptions?

7) What is the difference between final, finally and finalize?

JEE

8) What is the difference between web server and app server?

9) Explain the Struts1/Struts2/MVC application architecture?

10) What is the difference between forward and sendredirect?

General

11) How does a 3 tier application differ from a 2 tier one?

12) How does the version control process works?

13) What is the difference between JAR and WAR files?

Databases

14) What is a Left outer join?

15) What is the difference between UNION and UNION ALL?