ClassNotFoundException in my BusinessService class of MVC Web Application

Question

I am developing an MVC Web application.
I have a RegisterServlet in package org.prashansa.samsung and a RegisterService class in package org.prashansa.samsung.service.
I am creating an object of RegisterService in RegisterServlet. While executing the project it is throwing exception.Exception stack trace is as below:

May 28, 2017 12:11:51 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [org.prashansa.samsung.RegisterServlet] in context with path [/MyPortal] threw exception [Servlet execution threw an exception] with root cause
java.lang.ClassNotFoundException: org.hibernate.Session
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1333)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1167)
    at org.prashansa.samsung.RegisterServlet.doPost(RegisterServlet.java:44)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:94)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:502)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1104)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:684)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1519)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1475)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Unknown Source)

The error is coming in statement:
RegisterService reg = new RegisterService();
I've tried clean and build the project again. But, it didn't resolve the issue.
My RegisterService class is as follows:

package org.prashansa.samsung.service;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
import org.prashansa.samsung.dto.Employee;

public class RegisterService {

    public void register(Employee emp)
    {
        AnnotationConfiguration config = new AnnotationConfiguration();
        config.addAnnotatedClass(Employee.class);
        config.configure("hibernate.cfg.xml");

        SessionFactory factory = config.buildSessionFactory();
        Session session = factory.getCurrentSession();
        session.beginTransaction();

        session.save(emp);
        session.getTransaction().commit();
        return;
    }
}

Answer 1

I did the following:

myProject->Properties->Deployment Assembly->Add->Java Build Path Entries

This resolved my error.

Thank you all for your kind help.