OOP Concepts
Description of main Object Oriented Programming (OOP) concepts in Java - Encapsulation, Inheritance and Polymorphism.
Full lesson
Overloading and Overriding
What is method overloading and overriding, rules and examples. Difference between these two concepts. The main usage of overriding.
Full lesson
Lambda
Lambda expressions, method references, java.util.function interfaces: Predicate, Supplier, Consumer, Function, their primitive and binary specializations.
Full lesson
Inner Class
Features, syntax and examples of a regular inner class, a method-local inner class, an anonymous inner class and a static nested class.
Full lesson
Try-Catch
Using try-catch and finally block in Java. Handle multiple exceptions in one block. The AutoCloseable resource in the try-with-resources statement in Java 7.
Full lesson

Why should I learn Java?

Java has a rich API, which allows to solve different problems, but still is easy in learning. It has a lot of forums, resources and still is growing.

Comments
sad
Oct 20, 2012
Hi! Good site! Thanks.
unknown
Nov 22, 2012
good site,thanks for your knowledge sharing
unknown
Jan 15, 2013
I think this is a real great article post.Really thank you! Cool.
JWood
Feb 27, 2013
Hi! I cannot find search on the site. How can I find some information that I need use key e.g. "Optimistic locking"? Thanks
sysadmin
Feb 27, 2013
Hi JWood! There is no search on site now, but it will be implemented in the future.
Long
Mar 20, 2013
hi, I see that this site is written in Java. Do you use a framework? Do you use JPA or JDBC? According to you, how many request this website can handle in 1 second?
sysadmin
Mar 22, 2013
Hi, Long! The site is written using Servlets, EJB and JPA. I didn't calculated how many request the website can handle.
mrfreestyle
Aug 10, 2013
Great resource! Thank you for your work.
reeganf
Oct 17, 2013
Very useful for me
NDolgikh
May 22, 2015
Hi! It would be nice to be able to print quistions with answers for reading offline :)
sysadmin
May 12, 2016
Nataly, hope to add such feature in the future!:)
BadriaAch
Jul 8, 2016
thank your very much for your clarification ! it's very useful :)
sysadmin
Jul 8, 2016
BadriaAch, glad to be helpful!
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