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How to use JPA Entity with inheritance single table strategy in Spring Hibernate Framework
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Hints 
@Inheritance annotation by default strategy is SINGLE_TABLE. For all inhertied objects datas are getting stored in the same table. Type of object is get differed by discriminator column value.

Example
@Entity
@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name="CONSUMER_TYPE",discriminatorType=DiscriminatorType.STRING)
@DiscriminatorValue("General")
public class Consumer {...}
Web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>Hibernate016_InheritanceSingleTableStrategy</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
  <servlet>
    <servlet-name>beans</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>beans</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>
Output: SQL
create table Consumer
(CONSUMER_TYPE varchar(31) not null,
consumer_id integer not null auto_increment,
consumer_name varchar(255),
packName varchar(255),
callPlane varchar(255),
primary key (consumer_id)) ENGINE=InnoDB;
Output: Browser 
Project explorer preview 
Consumer.java
package com.knowledgewalls.entity;

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;

@Entity
@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name="CONSUMER_TYPE",discriminatorType=DiscriminatorType.STRING)
@DiscriminatorValue("General")
public class Consumer {
    @Id @GeneratedValue(strategy=GenerationType.AUTO)
    private int consumer_id;
    private String consumer_name;
    
    public int getConsumer_id() {
        return consumer_id;
    }
    public void setConsumer_id(int consumer_id) {
        this.consumer_id = consumer_id;
    }
    public String getConsumer_name() {
        return consumer_name;
    }
    public void setConsumer_name(String consumer_name) {
        this.consumer_name = consumer_name;
    }    
}
InternetConsumer.java
package com.knowledgewalls.entity;

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

@Entity
@DiscriminatorValue("iNet")
public class InternetConsumer extends Consumer {
    private String packName;

    public String getPackName() {
        return packName;
    }

    public void setPackName(String packName) {
        this.packName = packName;
    }    
}
PhoneConsumer.java
package com.knowledgewalls.entity;

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

@Entity
@DiscriminatorValue("iCall")
public class PhoneConsumer extends Consumer {
    private String callPlane;

    public String getCallPlane() {
        return callPlane;
    }
    public void setCallPlane(String callPlane) {
        this.callPlane = callPlane;
    }
}
ConsumerDAO.java
package com.knowledgewalls.dao;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

import com.knowledgewalls.entity.Consumer;
import com.knowledgewalls.entity.InternetConsumer;
import com.knowledgewalls.entity.PhoneConsumer;

@Repository
@Transactional
public class ConsumerDAO {
    
    @PersistenceContext
    EntityManager em;
    
    public void saveConsumer(Consumer consumer){
        try {
            em.persist(consumer);
        }
        catch(Exception e){
            e.printStackTrace();
        }
    }
    
    public void savePhoneConsumer(PhoneConsumer consumer){
        try {
            em.persist(consumer);
        }
        catch(Exception e){
            e.printStackTrace();
        }
    }
    
    public void saveInternetConsumer(InternetConsumer consumer){
        try {
            em.persist(consumer);
        }
        catch(Exception e){
            e.printStackTrace();
        }
    }
}
StudentInfoController.java
package com.knowledgewalls.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import com.knowledgewalls.dao.ConsumerDAO;
import com.knowledgewalls.entity.Consumer;
import com.knowledgewalls.entity.InternetConsumer;
import com.knowledgewalls.entity.PhoneConsumer;

@Controller
public class StudentInfoController {
    
    @Autowired
    ConsumerDAO consumerDAO;
    
    @RequestMapping(value="/addConsumers",method=RequestMethod.GET)
    public @ResponseBody String addUsers(){
        {
            Consumer consumer = new Consumer();
                consumer.setConsumer_name("Consumer");
            consumerDAO.saveConsumer(consumer);
            
            PhoneConsumer phoneConsumer = new PhoneConsumer();
                phoneConsumer.setConsumer_name("Phone Consumer");
                phoneConsumer.setCallPlane("smarter");
            consumerDAO.savePhoneConsumer(phoneConsumer);
            
            InternetConsumer internetConsumer = new InternetConsumer();
                internetConsumer.setConsumer_name("Internet Consumer");
                internetConsumer.setPackName("fast plus");
            consumerDAO.saveInternetConsumer(internetConsumer);
        }
        
        return "Consumer saved successfully!";
    }
}
Persistence.xml
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd" >

  <persistence-unit name="hibernatePersistenceUnit">
          <properties>
            <property name="hibernate.hbm2ddl.auto" value="create" />
        </properties>
  </persistence-unit>

</persistence>
Beans-servlet.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:util="http://www.springframework.org/schema/util"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd">

    <context:component-scan base-package="com.knowledgewalls" />
    <mvc:annotation-driven />
    <tx:annotation-driven transaction-manager="transactionManager" />
    
    <bean id="emf" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="persistenceXmlLocation" value="classpath*:persistence.xml" />
        <property name="persistenceUnitName" value="hibernatePersistenceUnit" />
        <property name="dataSource" ref="dataSource"/>
        <property name="jpaVendorAdapter" ref="jpaVendorAdapter"/>
    </bean>
    
    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
        <property name="url" value="jdbc:mysql://localhost:3306/test" />
        <property name="username" value="root" />
        <property name="password" value="mysql" />
        <property name="initialSize" value="5" />
        <property name="maxActive" value="10" />
    </bean>
    
    <bean id="jpaVendorAdapter" class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
        <property name="database" value="MYSQL"></property>
        <property name="showSql" value="true"></property>
        <property name="generateDdl" value="false"></property>
        <property name="databasePlatform" value="org.hibernate.dialect.MySQL5InnoDBDialect"></property>
    </bean>
    
    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
         <property name="entityManagerFactory" ref="emf" />
    </bean>
    
    <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" />
    <bean class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor"/>
    <bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>

</beans>
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