Hibernate One to One Mapping using XML
In this section, you will learn One to One mapping of table in Hibernate using Xml.
In, One to One mapping the record of one table have only one related record in the other table. For example , in the below example, each record of workerdetail table have only one related record in worker table. In other words, one address in the workerdetail table is related to only one employee or worker in the worker table.
EXAMPLE
In the given below example we will insert the data in two table in just one go. Both the table worker and workerdetail is attached with each other through foreign key worker_id field. In the below example, hibernate one to one mapping is done through annotation.
The project structure and jar file used is given below :
The sql query used to create the tables worker and workerdetail is given below :
CREATE TABLE `worker` ( `worker_id` bigint(10) NOT NULL auto_increment, `firstname` varchar(50) default NULL, `lastname` varchar(50) default NULL, `birth_date` date NOT NULL, `cell_phone` varchar(15) NOT NULL, PRIMARY KEY (`worker_id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 CREATE TABLE `workerdetail` ( `worker_id` bigint(20) NOT NULL auto_increment, `street` varchar(50) default NULL, `city` varchar(50) default NULL, `state` varchar(50) default NULL, `country` varchar(50) default NULL, PRIMARY KEY (`worker_id`), CONSTRAINT `FK_workerdetail` FOREIGN KEY (`worker_id`) REFERENCES `worker` (`worker_id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1
CODE
hibernate.cfg.xml ( /src/hibernate.cfg.xml )
<?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://192.168.10.13:3306/anky</property> <property name="connection.username">root</property> <property name="connection.password">root</property> <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">validate</property> </session-factory> </hibernate-configuration>
Worker.hbm.xml ( /src/net/roseindia/Worker.hbm.xml )
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="net.roseindia"> <class name="Worker" table="worker"> <id name="workerId" column="worker_id"> <generator class="native" /> </id> <one-to-one name="workerDetail" class="net.roseindia.WorkerDetail" cascade="save-update"></one-to-one> <property name="firstname" column="firstname" /> <property name="lastname" column="lastname" /> <property name="birthDate" type="date" column="birth_date" /> <property name="cellphone" column="cell_phone" /> </class> </hibernate-mapping>
WorkerDetail.hbm.xml ( /src/net/roseindia/WorkerDetail.hbm.xml )
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="net.roseindia"> <class name="WorkerDetail" table="workerdetail"> <id name="workerId" type="java.lang.Long"> <column name="worker_id" /> <generator class="foreign"> <param name="property">worker</param> </generator> </id> <one-to-one name="worker" class="net.roseindia.Worker" constrained="true"></one-to-one> <property name="street" column="street" /> <property name="city" column="city" /> <property name="state" column="state" /> <property name="country" column="country" /> </class> </hibernate-mapping>
Worker.java ( /src/net/roseindia/Worker.java )
package net.roseindia; import java.util.Date; public class Worker { private Long workerId; private String firstname; private String lastname; private Date birthDate; private String cellphone; private WorkerDetail workerDetail; public Worker() { } public Worker(String firstname, String lastname, Date birthdate, String phone) { this.firstname = firstname; this.lastname = lastname; this.birthDate = birthdate; this.cellphone = phone; } public Long getWorkerId() { return workerId; } public void setWorkerId(Long workerId) { this.workerId = workerId; } 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 Date getBirthDate() { return birthDate; } public void setBirthDate(Date birthDate) { this.birthDate = birthDate; } public String getCellphone() { return cellphone; } public void setCellphone(String cellphone) { this.cellphone = cellphone; } public WorkerDetail getWorkerDetail() { return workerDetail; } public void setWorkerDetail(WorkerDetail workerDetail) { this.workerDetail = workerDetail; } }
WorkerDetail.java( /src/net/roseindia/WorkerDetail.java )
package net.roseindia; public class WorkerDetail { private Long workerId; private String street; private String city; private String state; private String country; private Worker worker; public WorkerDetail() { } public WorkerDetail(String street, String city, String state, String country) { this.street = street; this.city = city; this.state = state; this.country = country; } public Long getWorkerId() { return workerId; } public void setWorkerId(Long workerId) { this.workerId = workerId; } public String getStreet() { return street; } public void setStreet(String street) { this.street = street; } public String getCity() { return city; } public void setCity(String city) { this.city = city; } public String getState() { return state; } public void setState(String state) { this.state = state; } public String getCountry() { return country; } public void setCountry(String country) { this.country = country; } public Worker getWorker() { return worker; } public void setWorker(Worker worker) { this.worker = worker; } }
ManageWorker.java ( /src/net/roseindia/ManageWorker.java )
package net.roseindia; import java.util.Date; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.List; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; import org.hibernate.service.ServiceRegistry; import org.hibernate.service.ServiceRegistryBuilder; public class ManageWorker { private static SessionFactory sf; private static ServiceRegistry serviceRegistry; @SuppressWarnings("unchecked") public static void main(String[] args) { try { Configuration configuration = new Configuration().addResource( "net/roseindia/Worker.hbm.xml").addResource( "net/roseindia/WorkerDetail.hbm.xml"); configuration.configure(); serviceRegistry = new ServiceRegistryBuilder().applySettings( configuration.getProperties()).buildServiceRegistry(); sf = configuration.buildSessionFactory(serviceRegistry); } catch (Throwable ex) { System.err.println("Failed to create sessionFactory object." + ex); throw new ExceptionInInitializerError(ex); } System.out .println("Example : Hibernate One to One Mapping using Xml "); Session session = sf.openSession(); session.beginTransaction(); // For passing Date of birth as String SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); Date dob = null; try { dob = sdf.parse("1987-05-21"); } catch (ParseException e) { e.printStackTrace(); } Worker worker = new Worker("Sushmita", "Dasgupta", dob, "919595959595"); WorkerDetail workerDetail = new WorkerDetail("Lake Town", "Kolkata", "West Bengal", "India"); worker.setWorkerDetail(workerDetail); workerDetail.setWorker(worker); session.save(worker); List<Worker> workerList = session.createQuery("from Worker").list(); for (Worker work1 : workerList) { System.out.println(work1.getFirstname() + " , " + work1.getLastname() + ", " + work1.getWorkerDetail().getState()); } session.getTransaction().commit(); session.close(); } }
OUTPUT
In the console, you will get the following :
Example : Hibernate One to One Mapping using Xml Hibernate: insert into worker (firstname, lastname, birth_date, cell_phone) values (?, ?, ?, ?) Hibernate: select worker0_.worker_id as worker1_0_, worker0_.firstname as firstname0_, worker0_.lastname as lastname0_, worker0_.birth_date as birth4_0_, worker0_.cell_phone as cell5_0_ from worker worker0_ Sushmita , Dasgupta, West Bengal Hibernate: insert into workerdetail (street, city, state, country, worker_id) values (?, ?, ?, ?, ?)
In worker table, you will get the following records :
In WorkerDetail table you will get the following records :