Entity Manager: Join Transaction : Entity Manager « EJB3 « Java Tutorial

1. Java Tutorial
2. EJB3
3. Entity Manager

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.ejb.TransactionAttribute;
import javax.ejb.TransactionAttributeType;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceContextType;

@Stateful
@TransactionAttribute(TransactionAttributeType.REQUIRES_NEW)
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");
    manager.joinTransaction();
    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();
    


  }

}

27.14.Entity Manager
	27.14.1.	Use Entity Manager To Persist Save Entity Bean
	27.14.2.	Entity Manager: Join Transaction