hb : Many to Many Using Annotation

Address.java
============

package mypack;

import java.util.Set;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.Table;

@Entity
@Table(name="address")
public class Address 
{
@Id
@Column(name="addrId")
private int addrId;
@Column(name="city",length=10)
private String city;
@ManyToMany(targetEntity=Employee.class,mappedBy="addresses")
private Set  employees;

    public Set getEmployees() {
        return employees;
    }

    public void setEmployees(Set employees) {
        this.employees = employees;
    }


    public int getAddrId() {
        return addrId;
    }

    public void setAddrId(int addrId) {
        this.addrId = addrId;
    }
        

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

}




Employee.java
=============

package mypack;

import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;
import javax.persistence.Table;
@Entity
@Table(name="Employee")
public class Employee 
{
@Id
@Column(name="empId")
private int empId;
@Column(name="empname",length=10)
private String name;
@ManyToMany(targetEntity=Address.class,cascade=CascadeType.ALL) 
@JoinTable(name="emp_addr",joinColumns=@JoinColumn(name="empId_fk",referencedColumnName="empId"),inverseJoinColumns=@JoinColumn(name="addrId_fk",referencedColumnName="addrId"))
private Set addresses;

    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 Set getAddresses() {
        return addresses;
    }

    public void setAddresses(Set addresses) {
        this.addresses = addresses;
    }
}


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>
    <property name="hibernate.dialect">org.hibernate.dialect.DerbyDialect</property>
    <property name="hibernate.connection.driver_class">org.apache.derby.jdbc.ClientDriver</property>
    <property name="hibernate.connection.url">jdbc:derby://localhost:1527/mydata</property>
    <property name="hibernate.connection.username">app</property>
    <property name="hibernate.connection.password">app</property>
    <property name="show_sql">true</property>
    <property name="hbm2ddl.auto">create</property>
<mapping class="mypack.Address"></mapping>
<mapping class="mypack.Employee"></mapping> 
    
  </session-factory>
</hibernate-configuration>



OurLogic.java
=============

package mypack;

import java.util.HashSet;
import java.util.Set;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration;

public class OurLogic { 

public static void main(String args[])
{

//SessionFactory factory = new Configuration().configure().buildSessionFactory();
            SessionFactory factory = new AnnotationConfiguration().configure().buildSessionFactory();
Session ses = factory.openSession();

Employee emp1 = new Employee();
emp1.setEmpId(1);
emp1.setName("Hari");

Employee emp2=new Employee();
emp2.setEmpId(2);
emp2.setName("Krishna");

Address addr1=new Address();
Address addr2 = new Address();

addr1.setAddrId(101);
addr1.setCity("Bangalore");

addr2.setAddrId(102);
addr2.setCity("Chennai");

Set  s =new HashSet();
s.add(addr1);
s.add(addr2);

emp1.setAddresses(s);
emp2.setAddresses(s);

Transaction tx = ses.beginTransaction();
ses.save(emp1);
ses.save(emp2);
tx.commit();
System.out.println("Man to Many using annotations been done...!!!!!");
ses.close();
}

}