EJB3 Java Tutorial

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File: Customer.java

import javax.persistence.Entity;
import javax.persistence.EntityListeners;
import javax.persistence.Id;
import javax.persistence.PostRemove;
@Entity
public class Customer implements java.io.Serializable {
  private String firstName;
  private String lastName;
  @Id
  private long ssn;
  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 long getSsn() {
    return ssn;
  }
  public void setSsn(long ssn) {
    this.ssn = ssn;
  }
}
File: EmployeeBean.java

import javax.ejb.Stateful;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceContextType;
@Stateful
public class EmployeeBean implements EmployeeServiceLocal, EmployeeServiceRemote {
  @PersistenceContext(unitName="EmployeeService",
      type=PersistenceContextType.EXTENDED)
  private EntityManager manager;
  public void doAction() {
    Customer cust = new Customer();
    cust.setFirstName("Joe");
    manager.persist(cust);
    
    System.out.println("Saved");
    
    cust = manager.find(Customer.class,cust.getSsn());
    
    System.out.println(cust.getFirstName());
    cust.setFirstName("new Name");
    
    manager.merge(cust);
    cust = manager.find(Customer.class,cust.getSsn());
    
    System.out.println(cust.getFirstName());
  }
}
File: EmployeeServiceLocal.java

import javax.ejb.Local;
@Local
public interface EmployeeServiceLocal {
  public void doAction();
}
File: EmployeeServiceRemote.java

import javax.ejb.Remote;
@Remote
public interface EmployeeServiceRemote {
  public void 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
File: Main.java

import javax.ejb.EJB;
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("EmployeeBean/remote");
    service.doAction();
    
  }
}