HttpSession interface is defined in "javax.servlet.http" package
and is used for the purpose of session tracking while working with servlets.
Session tracking is a mechanism that is used to maintain state about a series
of requests from the same user (that is, requests originating from the same
browser) across some period of time.
HttpServletRequest interface is defined in "javax.servlet.http"
and is used to retrieve parameters from the request, HTTP request header
information, cookies from the request, getting session object to maintain
session for the request etc.
HttpServlet class is an abstract class defined in "javax.servlet.http"
package and is sub class of GenericServlet class defined in "javax.servlet"
package. GenericServlet class is used to define a generic,
protocol-independent servlet but HttpServlet class provides an HTTP protocol
Hibernate is popular, powerful, high performance, open source object
relational mapping tool for Java platform. Hibernate maps java classes to
database tables and provides data query and retrieval facilities also which
can reduce much development time in compare to manual data handling in SQL
Java hello world
Java is a high-level object-oriented programming language developed by the
Sun Microsystems and is available in different form like JSP, Java Applets,
J2EE, JavaBeans, Mobile Java.
Hibernate is an open source software that provides
object-relational mapping library for the java language by mapping an
object-oriented domain model to a traditional relational database with the help
of a framework.
The JVM's heap stores all the objects
generating by a running Java
program. Java uses the new operator to create objects and memory for
new objects is allocated on the heap at run time.