Java/EJB3/Entity Primary Key
EJB Tutorial from JBoss: Primary Key Composition
<source lang="java">
File: Customer.java /*
* JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */
package org.jboss.tutorial.ruposite.bean; import java.util.Set; import javax.persistence.CascadeType; import javax.persistence.EmbeddedId; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.ManyToMany; import javax.persistence.Transient; import javax.persistence.JoinTable; import javax.persistence.JoinColumn; /**
* */
@Entity public class Customer implements java.io.Serializable {
CustomerPK pk;
Set<Flight> flights;
public Customer()
{
}
@EmbeddedId
public CustomerPK getPk()
{
return pk;
}
public void setPk(CustomerPK pk)
{
this.pk = pk;
}
@Transient
public String getName()
{
return pk.getName();
}
@ManyToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE}, fetch = FetchType.EAGER, mappedBy="customers")
@JoinTable(name="flight_customer_table",
joinColumns = {@JoinColumn(name = "FLIGHT_ID")},
inverseJoinColumns = {@JoinColumn(name = "CUSTOMER_ID"), @JoinColumn(name = "CUSTOMER_NAME")})
public Set<Flight> getFlights()
{
return flights;
}
public void setFlights(Set<Flight> flights)
{
this.flights = flights;
}
}
File: CustomerPK.java /*
* JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */
package org.jboss.tutorial.ruposite.bean; import javax.persistence.Embeddable; import javax.persistence.Embeddable; /**
* Comment * * @author
Use Combined Fields As Primary Key
<source lang="java">
File: EmployeeService.java
import java.util.Collection; import javax.ejb.Remove; import javax.ejb.Stateless; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; import javax.persistence.Query; @Stateless public class EmployeeService implements EmployeeServiceLocal, EmployeeServiceRemote {
@PersistenceContext(unitName="EmployeeService")
EntityManager em;
public EmployeeService() {
}
public void doAction(){
Employee cust = new Employee();
cust.setFirstName("B");
cust.setLastName("B");
cust.setSsn(9999999);
em.persist(cust);
em.flush();
}
}
File: EmployeeServiceLocal.java
import java.util.Collection; import javax.ejb.Local; @Local public interface EmployeeServiceLocal {
public void doAction();
}
File: EmployeeServiceRemote.java
import java.util.Collection;
import javax.ejb.Remote;
@Remote
public interface EmployeeServiceRemote{
public void doAction();
}
File: Employee.java import java.io.Serializable; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.IdClass; import javax.persistence.Table; @Entity @Table(name="EMP") @IdClass(EmployeePK.class) public class Employee implements Serializable {
private String firstName;
private String lastName;
private long ssn;
public String getFirstName() { return firstName; }
public void setFirstName(String firstName) { this.firstName = firstName; }
@Id
public String getLastName() { return lastName; }
public void setLastName(String lastName) { this.lastName = lastName; }
@Id
public long getSsn() { return ssn; }
public void setSsn(long ssn) { this.ssn = ssn; }
public String toString() {
return "Employee : " + getFirstName() ;
}
}
File: EmployeePK.java public class EmployeePK implements java.io.Serializable {
private String lastName;
private long ssn;
public EmployeePK() {
}
public EmployeePK(String lastName, long ssn) {
this.lastName = lastName;
this.ssn = ssn;
}
public String getLastName() {
return this.lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public long getSsn() {
return ssn;
}
public void setSsn(long ssn) {
this.ssn = ssn;
}
public boolean equals(Object obj) {
if (obj == this)
return true;
if (!(obj instanceof EmployeePK))
return false;
EmployeePK pk = (EmployeePK) obj;
if (!lastName.equals(pk.lastName))
return false;
if (ssn != pk.ssn)
return false;
return true;
}
public int hashCode() {
return lastName.hashCode() + (int) ssn;
}
}
File: Main.java import java.util.Collection; import javax.naming.InitialContext;
public class Main {
public static void main(String[] a) throws Exception {
EmployeeServiceRemote service = null;
// Context compEnv = (Context) new InitialContext().lookup("java:comp/env");
// service = (HelloService)new InitialContext().lookup("java:comp/env/ejb/HelloService");
service = (EmployeeServiceRemote) new InitialContext().lookup("EmployeeService/remote");
service.doAction();
}
}
File: jndi.properties java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory java.naming.factory.url.pkgs=org.jboss.naming:org.jnp.interfaces java.naming.provider.url=localhost:1099
</source>
