Hibernate Table Per Hierarchy

Add following dependency in pom.xml file.

<dependencies>

<dependency>
	<groupId>org.hibernate</groupId>
	<artifactId>hibernate-core</artifactId>
	<version>5.4.28.Final</version>
</dependency>

<dependency>
	<groupId>mysql</groupId>
	<artifactId>mysql-connector-java</artifactId>
	<version>5.1.6</version>
</dependency>

</dependencies>
  

hibernate.cfg.xml

   <?xml version = "1.0" encoding = "utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
    "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
     "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
<session-factory>

<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/stds</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">root</property>

<property name="hbm2ddl.auto">update</property>
<property name="show_sql">true</property>
		
	
</session-factory>
</hibernate-configuration>
   

Person.java

package com.deepsingh44.model;

import javax.persistence.DiscriminatorColumn;
import javax.persistence.DiscriminatorType;
import javax.persistence.DiscriminatorValue;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.InheritanceType;
import javax.persistence.Table;

@Entity
@Table(name = "tph")
@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name="role",
discriminatorType=DiscriminatorType.STRING)
@DiscriminatorValue(value="person")
public class Person {
	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	private int id;
	private String name;

	public int getId() {
		return id;
	}

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

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

}
  

Employee.java

package com.deepsingh44.model;

import javax.persistence.DiscriminatorValue;
import javax.persistence.Entity;

@Entity
@DiscriminatorValue(value="employee")
public class Employee extends Person {
	private float salary;

	public float getSalary() {
		return salary;
	}

	public void setSalary(float salary) {
		this.salary = salary;
	}

}
  

Student.java

package com.deepsingh44.model;

import javax.persistence.DiscriminatorValue;
import javax.persistence.Entity;

@Entity
@DiscriminatorValue(value="student")
public class Student extends Person {
	private float marks;

	public float getMarks() {
		return marks;
	}

	public void setMarks(float marks) {
		this.marks = marks;
	}

}
  

Test.java

package com.deepsingh44.model;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.Metadata;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;

public class Test {
	public static void main(String[] args) {
	// Load your configuration file
	StandardServiceRegistry ssr = new StandardServiceRegistryBuilder().
			configure("hibernate.cfg.xml").
			build();
	Metadata meta = new MetadataSources(ssr).
			addAnnotatedClass(Person.class).
			addAnnotatedClass(Student.class)
			.addAnnotatedClass(Employee.class).
			getMetadataBuilder().
			build();

	// Get sessionFactory object
	SessionFactory factory = meta.
			getSessionFactoryBuilder().
			build();

	// Get session object
	Session session = factory.openSession();
		
	Person p=new Person();
	p.setName("Mala");
		
	Employee emp=new Employee();
	emp.setName("Sujeet");
	emp.setSalary(50000);
		
	Student s=new Student();
	s.setName("Rohit");
	s.setMarks(78.8f);
		
	session.save(p);
	session.save(emp);
	session.save(s);
		
	session.beginTransaction().commit();
		
	System.out.println("successfully ");
			
	}
}
  

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