Exception in thread "main" org.hibernate.MappingException: Unknown entity: com.contact.model.Contact

package com.contact;



import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.channels.FileLock;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;

import com.contact.model.Contact;

public class Application {

    //Session factory
    private static final SessionFactory sessionFactory = buildSesssionFactory();

    public static void main(String[] args) throws InterruptedException {

        System.out.println("Session factory");
        Contact contact = new Contact.ContactBuilder("Bob", "Marley").withEmail("bob.nik@gmail.com").withPhone(5859789733L).build();

        //Open a Session
        System.out.println("Open a Session");
        Session session = sessionFactory.openSession();

        //Begin a Transaction
        System.out.println("Begin a Transaction");
         session.beginTransaction();


        //Use the session to save the contact
        System.out.println("Use the session to save the contact");
        session.save(contact);
        //Commit the transaction
        System.out.println("Commit the transaction");
        session.getTransaction().commit();
        // Close the session
        System.out.println("Close the session");
        session.close();
    }

    private static SessionFactory buildSesssionFactory() {
        // Create a StandardServiceRegistry
        Configuration configuration = new Configuration();
        configuration.addAnnotatedClass(com.contact.model.Contact.class);
        configuration.setProperty("hibernate.temp.use_jdbc_metadata_defaults","false");
        configuration.configure();

        final ServiceRegistry registry = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();
        return new org.hibernate.boot.MetadataSources(registry).buildMetadata().buildSessionFactory();


    }

    static boolean isLocked(String fileName) {
        try {
            RandomAccessFile f = new RandomAccessFile(fileName, "r");
            try {
                FileLock lock = f.getChannel().tryLock(0, Long.MAX_VALUE, true);
                if (lock != null) {
                    lock.release();
                    return false;
                }
            } finally {
                f.close();
            }
        } catch (IOException e) {
            // ignore
        }
        return true;
    }

}

package com.contact.model;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name="CONTACT")
public class Contact {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;

    @Column
    private String firstName;

    @Column
    private String lastName;

    @Column
    private String email;

    @Column
    private Long phone;

    public Contact() {
    }

    public Contact(ContactBuilder contactBuilder) {
        this.firstName = contactBuilder.firstName;
        this.lastName = contactBuilder.lastName;
        this.email = contactBuilder.email;
        this.phone=contactBuilder.phone;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public Long getPhone() {
        return phone;
    }

    public void setPhone(Long phone) {
        this.phone = phone;
    }

    @Override
    public String toString() {
        return "Contact [id=" + id + ", firstName=" + firstName + ", lastName=" + lastName + ", email=" + email
                + ", phone=" + phone + "]";
    }

    public static class ContactBuilder {

        private String firstName;

        private String lastName;

        private String email;

        private Long phone;

        public ContactBuilder(String firstName, String lastName) {
            this.firstName = firstName;
            this.lastName = lastName;
        }

        public ContactBuilder withEmail(String email) {
            this.email = email;
            return this;

        }

        public ContactBuilder withPhone(Long phone) {
            this.phone = phone;
            return this;

        }

        public Contact build() {

            return new Contact(this);
        }

    }

}