[list]switch case variables accepting the string literals
Allowing underscores in between digits. Numeric value is more readable when we use underscores in between (e.g. Debit card or credit card number is 16 digit so if you use underscore in between for every 4 digits).
Serialization is the process of persisting an object state in a flat file or sending through network.
Mean converting the java object into bits and bytes, because hard disks or networks understands only these bits and bytes, cannot understand the data in terms of objects
Real time scenarios
Storing the object state in a disk. Object state means instance variable values at particular time.
Sending the object through network (One JVM to another JVM)
Storing the object in database (In Hibernate we can directly send object 'save()' method to insert the values in data base).
With my knowledge Every class that extends GenericSerlvet or HttpServlet should be treated as a servelt by the server.
I have reviewed your servelt, but I didnt see any problems with your servlet. Have you configured your servelt in web.xml ?