Shubhendu Pramanik.

Hi Vimal,
your code looks fine however make sure that you are using the @Id annotation on the variable only and not on getter method of the Entity object.
If you are using @Id in the getter then all the annotations(@Column) must be put on the getters of the attributes(irrespective of whether the attribs are of Entity or Embedded object) i.e. if you are using @ID at the getter method make the @Column on getters of other attributes and if on field then use @Column on fields only.

I faced the same issue.
Try this, it will work.

Set environment variables like below(put your local path)

JAVA_HOME = C:\Program Files\Java\jdk1.8.0_45
CLASSPATH = .;C:\Program Files\Java\jdk1.8.0_45\bin
PATH = C:\Program Files\Java\jdk1.8.0_45\bin

If even after doing so it doesn't work, there must be an older version of java installed on your machine too. Find and remove that one.

Thank you very much for the answers. Its clear now.

I think my concept is not clear about synchronization and singleton object. What is the difference between synchronized method and singleton object's method ?
Thanks in advance.

State means at any particular time the values that an object hold. You can think it like an instance/object of a class holding some values at a particular time. So that is the state of that object. State transfer means transferring these values to a particular component.

REST is stateless because each request is self explanatory i.e. each request contains all the information that is needed by the requested resource and it does not depend on any previous state. Below link might help you on this...

https://looselyconnected.wordpress.com/2011/02/07/rest-what-is-state-anyway/

Is OCA/OCP(1z0-808/1z0-809) certifications for freshers only ? Does it help or an add on for experienced(1.5-2 years) in getting new job(switch). If not then what is the suitable certification.
Please help me on this. Thanks in advance.

Is 1Z0-808(Programmer I) certification is enough to get a good job or 1Z0-809(Programmer II) is must? Also is it must to pass 1Z0-808(Programmer I) test to be able to sit for 1Z0-809(Programmer II) test ?

I have another query. For both of these I have to register separately ? That means registration fees will be Rs. 9604 (1Z0-808) + Rs. 9604 (1Z0-809) i.e. total of Rs. 19208 ?

I think my doubt is clear now. If I am not wrong I have to pass 1Z0-808(Programmer I) first and then 1Z0-809(Programmer II).
Thank you once again

See if below link could help you on this...

http://www.programmerinterview.com/index.php/java-questions/interface-vs-abstract-class/

This may sound little stupid, but are Associate and programmer two different certifications? Can I sit for both of these together ? Could you please send me some informative links. Thanks very much again.

I have been working with a company as java developer for last 1.6 years. I have hands on product development experience in Core java(mostly), JSP/Servlet. Also I have basic knowledge of Spring and Hibernate. But they are putting me in salesforce related project. When I switch company I want to work in java related project. So if I work on salesforce say for next 1 year and then switch with OCJP certification will it help me getting good job?
Any suggestion would mean a lot to me. I am confused. Thank you in advance.

Thank you Simon for this valuable information. I have another query. Can I directly sit for OCJP 7/8 or before that I need to pass any other exams ?

I have 1+ year of developer experience in core java. If I do OCJP/OCPJP certification will it help me getting good hike or on new job/ interviews. Also please let me know which certification should I do, OCJP/OCJP ? Also please let me know whether I should do OCJP 7 or 8 . Thank you in advance.