Some question asked by interviewer to me

Question

Please look at some questions and post your most valuable thoughts.
1). Can we create instance of interface or not if yes then how?
Answer by me: I gave wrong answer.
2). Java is comiled langauge or interpreted langauge if compiled langauge then which compiler.....?
Answer by me: Java is compiled and interpreted langauge and javac compiler and java interpreter is used.
3). Encapsulation and datahiding is same? if not so tell difference.
Answer by me: In case of Encapsulation only data which donot contribute its essential characteristics will be hiding and only data hiding means all data will be hide.Thats the difference b/w these two.
Interviewer also told me coding example of encapsulation. But I have not good example of that.
4).Difference b/w awt and swing?
Answer by me: Both awt and swing is used in applet but only difference b/w these two is- swing will give better look of label and buttons.
5).What is syncronization and why we use syncronization in multithreading?
Answer by me: Syncronization is used to prevent deadlock condition in multithreading.
I was not the correct answer of "what is syncronization?"
Please post your thoughts on any of 5 questions. I am also trying to findout answers.
thanks
Edited by: shobhit_onprob on Apr 18, 2009 5:05 AM

Answer 1

shobhit_onprob wrote:
Please look at some questions and post your most valuable thoughts.
1). Can we create instance of interface or not if yes then how?
Answer by me: I gave wrong answer.Instances of classes implementing an interface are considered instances of that interface ("is-a").
2). Java is comiled langauge or interpreted langauge if compiled langauge then which compiler.....?
Answer by me: Java is compiled and interpreted langauge and javac compiler and java interpreter is used.Java source code is compiled to byte code. That byte code can be executed in any way (the Java spec doesn't say how). It may be interpreted.
3). Encapsulation and datahiding is same? if not so tell difference.
Answer by me: In case of Encapsulation only data which donot contribute its essential characteristics will be hiding and only data hiding means all data will be hide.Thats the difference b/w these two.In my opinion Encapsulation is more than just data hiding. You can also encapsulate behaviour, for example.
4).Difference b/w awt and swing?
Answer by me: Both awt and swing is used in applet but only difference b/w these two is- swing will give better look of label and buttons.AWT is the "old" GUI toolkit that uses native controls of the environment it runs it.
Swing is the "new" GUI toolkit that draws its controls in pure Java code and uses AWT as the underlying base.
5).What is syncronization and why we use syncronization in multithreading?
Answer by me: Syncronization is used to prevent deadlock condition in multithreading.
I was not the correct answer of "what is syncronization?"No. synchronization can lead to deadlocks.
synchronization is used to ensure that data is only accessed when it is in a consistent state.