Inheritance mapping in hibernate :Table per class

This mapping is not known as good mapping for projects. In this approach all of the fields of each type in the inheritance hierarchy are stored in distinct tables.
It has many drawbacks while dealing with polymorphic and association. This strategy supports bidirectional one-to-many association.

package domain;
import javax.persistence.*;
@Entity
@Inheritance(strategy=InheritanceType.TABLE_PER_CLASS)
public class Employee{
    private int empId;
    private String name;
    private String email;
    @Id 
    public int getEmpId() {
        return empId;
    }
    public void setEmpId(int empId) {
        this.empId = empId;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
    
}

package domain;
import javax.persistence.*;
@Entity
public class FullTimeEmployee extends Employee{
    private String designation;
    private String empCode;
    public String getDesignation() {
        return designation;
    }
    public void setDesignation(String designation) {
        this.designation = designation;
    }
    public String getEmpCode() {
        return empCode;
    }
    public void setEmpCode(String empCode) {
        this.empCode = empCode;
    }
    @Override
    public String toString() {
        return "FullTimeEmployee [designation=" + designation + ", empCode="
                + empCode + ", getEmpId()=" + getEmpId() + ", getName()="
                + getName() + ", getEmail()=" + getEmail() + "]";
    }
    
}

package domain;
import javax.persistence.*;
@Entity
public class PartTimeEmployee extends Employee{
    private int duration;
    private String reportTo;
    public int getDuration() {
        return duration;
    }
    public void setDuration(int duration) {
        this.duration = duration;
    }
    public String getReportTo() {
        return reportTo;
    }
    public void setReportTo(String reportTo) {
        this.reportTo = reportTo;
    }
    @Override
    public String toString() {
        return "PartTimeEmployee [duration=" + duration + ", reportTo="
                + reportTo + ", getEmpId()=" + getEmpId() + ", getName()="
                + getName() + ", getEmail()=" + getEmail() + "]";
    }
     
}

import org.hibernate.Session;
import org.hibernate.cfg.AnnotationConfiguration;

import domain.FullTimeEmployee;
import domain.PartTimeEmployee;

public class Operations {
    public static void create() {
        System.out.println("############## Create ##############");
        Session session = new AnnotationConfiguration().configure()
                .buildSessionFactory().openSession();
        session.beginTransaction();
        PartTimeEmployee pe = new PartTimeEmployee();
        pe.setEmpId(1);
        pe.setName("abc");
        pe.setEmail("abc@rmail.com");
        pe.setDuration(4);
        pe.setReportTo("PM");
        session.save(pe);

        FullTimeEmployee fe = new FullTimeEmployee();
        fe.setEmpId(2);
        fe.setName("ssd");
        fe.setDesignation("manager");
        fe.setEmail("mail@email.com");
        fe.setEmpCode("86789");
        session.save(fe);

        session.getTransaction().commit();
    }

    public static void read() {
        System.out.println("############## Read ##############");
        Session session = new AnnotationConfiguration().configure()
                .buildSessionFactory().openSession();
        session.beginTransaction();
        System.out.println("########### load contact and person");
        PartTimeEmployee pe = (PartTimeEmployee) session.load(
                PartTimeEmployee.class1);
        FullTimeEmployee fe = (FullTimeEmployee) session.load(
                FullTimeEmployee.class2);
        System.out.println(pe);
        System.out.println(fe);
        session.getTransaction().commit();
    }

    public static void update() {
        System.out.println("############## Update ##############");
        Session session = new AnnotationConfiguration().configure()
                .buildSessionFactory().openSession();
        // TODO
        session.getTransaction().commit();
    }

    public static void delete() {
        System.out.println("############## Delete ##############");
        Session session = new AnnotationConfiguration().configure()
                .buildSessionFactory().openSession();
        session.beginTransaction();
        // TODO
        session.getTransaction().commit();
    }

    public static void main(String[] args) {
        create();
        read();
        // update();
        // delete();
    }
}


<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
                                         "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <!-- Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/test</property>
        <property name="connection.username">root</property>
        <property name="connection.password" />
        <property name="connection.pool_size">1</property>
        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
        <property name="current_session_context_class">thread</property>
        <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
        <property name="show_sql">true</property>
        <property name="hbm2ddl.auto" >update</property>
        <mapping class="domain.Employee"/>
        <mapping class="domain.PartTimeEmployee"/>
        <mapping class="domain.FullTimeEmployee"/>
    </session-factory>
</hibernate-configuration>


TABLES  AFTER EXECUTION




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