Entity class not found error

Question

Im new to java EJB ,Im getting this erro. i think its regarding entity class. can some one help me to fix this issue, thanks a lot.

Warning:   StandardWrapperValve[registrationsServlet]: Servlet.service() for servlet registrationsServlet threw exception
java.lang.NoClassDefFoundError: Entity/Userdetailcb006116
    at com.themePark.servlets.registrationsServlet.processRequest(registrationsServlet.java:66)
    at com.themePark.servlets.registrationsServlet.doGet(registrationsServlet.java:88)

    ... more

here is the my servlet codes, it looks like ok to me but, compiler does'nt identify Userdetailcb006116 as entity class. is there any way to make object of it or ?

import Entity.Userdetailcb006116;
import Sessions.Userdetailcb006116FacadeLocal;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.ejb.EJB;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


public class registrationsServlet extends HttpServlet {
    @EJB
    private Userdetailcb006116FacadeLocal userdetailcb006116Facade;


    protected void processRequest(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        resp.setContentType("text/html;charset=UTF-8");
        try (PrintWriter out = resp.getWriter()) {

        String fname = req.getParameter("fName");
        String lname = req.getParameter("lName");
        // here im getting error, although this entity class, compiler doesnt recognize as this a entity class i think 
        Userdetailcb006116 us = new Userdetailcb006116(fname, lname);
        userdetailcb006116Facade.create(us);

        RequestDispatcher rd = req.getRequestDispatcher("index.jsp");
                rd.forward(req, resp);
        }
    }

Entity class code :

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package Entity;

import java.io.Serializable;
import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import javax.xml.bind.annotation.XmlRootElement;

/**
 *
 * @author H4k3r
 */
@Entity
@Table(name = "USERDETAILSCB006116")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Userdetailscb006116.findAll", query = "SELECT u FROM Userdetailscb006116 u"),
    @NamedQuery(name = "Userdetailscb006116.findByFname", query = "SELECT u FROM Userdetailscb006116 u WHERE u.fname = :fname"),
    @NamedQuery(name = "Userdetailscb006116.findByLname", query = "SELECT u FROM Userdetailscb006116 u WHERE u.lname = :lname")})
public class Userdetailscb006116 implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 100)
    @Column(name = "FNAME")
    private String fname;
    @Size(max = 100)
    @Column(name = "LNAME")
    private String lname;

    public Userdetailscb006116() {
    }

    public Userdetailscb006116(String fname) {
        this.fname = fname;
    }

    public String getFname() {
        return fname;
    }

    public void setFname(String fname) {
        this.fname = fname;
    }

    public String getLname() {
        return lname;
    }

    public void setLname(String lname) {
        this.lname = lname;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (fname != null ? fname.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof Userdetailscb006116)) {
            return false;
        }
        Userdetailscb006116 other = (Userdetailscb006116) object;
        if ((this.fname == null && other.fname != null) || (this.fname != null && !this.fname.equals(other.fname))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "Entity.Userdetailscb006116[ fname=" + fname + " ]";
    }

}

facade code:

import Entity.Userdetailscb006116;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

/**
 *
 * @author H4k3r
 */
@Stateless
public class Userdetailscb006116Facade extends AbstractFacade<Userdetailscb006116> implements Userdetailscb006116FacadeLocal {
    @PersistenceContext(unitName = "cb006116_ThemePark-ejbPU")
    private EntityManager em;

    @Override
    protected EntityManager getEntityManager() {
        return em;
    }

    public Userdetailscb006116Facade() {
        super(Userdetailscb006116.class);
    }

}