Important Concepts

Important Java Questions:

1) Difference betweeen Class, Object and Instance
Link is -> http://alfredjava.wordpress.com/2008/07/08/class-vs-object-vs-instance/
http://wiki.answers.com/Q/Difference_between_instance_and_object#slide=2

2) super keyword with example

The super is a reference variable that is used to refer immediate parent class object.

Whenever you create the instance of subclass, an instance of parent class is created implicitly 
i.e. referred by super reference variable.

Usage of super Keyword:
-> super is used to refer immediate parent class instance variable.
-> super() is used to invoke immediate parent class constructor. 
super() is added in each class constructor automatically by compiler.
Please see the link: http://www.javatpoint.com/super-keyword
-> super is used to invoke immediate parent class method.

Examples given in this link.  Source: http://www.javatpoint.com/super-keyword


3) Difference between Error and Exceptions(Clearly explained in the Youtube Channel "SharingIsLearning"
in the video titled as "Exception Handling"
Link is -> https://www.youtube.com/watch?v=vjmMF9ZZkiQ