Spring MVC validation

1. spring boot starter web dependency already includes hibernate validator dependency.
2.  https://www.journaldev.com/2668/spring-validation-example-mvc-validator
3. http://technicalstack.com/form-validation-part-4-using-annotation-pattern-past-max-etc/
4. https://stackoverflow.com/questions/3813195/regular-expression-for-indian-mobile-numbers
5. mobile no validation
6. birthdate validation for correct range which dependes on gender
7. email validation
8. https://docs.oracle.com/javase/tutorial/essential/regex/intro.html
9.