Use PersistenceContext annotation to Link Persistence Context : Persistence « EJB3 « Java






Use PersistenceContext annotation to Link Persistence Context


File: EmployeeService.java


import java.util.Collection;

import javax.annotation.Resource;
import javax.ejb.Stateless;
import javax.ejb.TransactionAttribute;
import javax.ejb.TransactionAttributeType;
import javax.ejb.TransactionManagement;
import javax.ejb.TransactionManagementType;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import javax.transaction.UserTransaction;

@Stateless
public class EmployeeService implements EmployeeServiceLocal, EmployeeServiceRemote {
  @PersistenceContext(unitName="EmployeeService")
  EntityManager em;
  
  public EmployeeService() {
  }

  public Employee createEmployee(int id, String name, long salary, byte[] pic) {
    Employee emp = new Employee(id);
    emp.setName(name);
    emp.setSalary(salary);
    emp.setPicture(pic);
    
    em.persist(emp);
    
    
    emp = findEmployee(id);
    System.out.println(emp);
    
    return emp;
  }

  public void removeEmployee(int id) {
    Employee emp = findEmployee(id);
    if (emp != null) {
      em.remove(emp);
    }
  }

  public Employee raiseEmployeeSalary(int id, long raise) {
    Employee emp = em.find(Employee.class, id);
    if (emp != null) {
      emp.setSalary(emp.getSalary() + raise);
    }
    return emp;
  }

  public Employee findEmployee(int id) {
    return em.find(Employee.class, id);
  }

  public Collection<Employee> findAllEmployees() {
    Query query = em.createQuery("SELECT e FROM Employee e");
    return (Collection<Employee>) query.getResultList();
  }
  
  public void doAction(){
    Employee emp = new Employee(1);
    emp.setName("name");
    emp.setSalary(100);
    emp.setPicture("pic".getBytes());
    
    em.persist(emp);
    
    
    emp = findEmployee(1);
    System.out.println(emp);
  }

}

    


File: EmployeeServiceLocal.java



import javax.ejb.Local;

@Local
public interface EmployeeServiceLocal {
    public void doAction();
  public Employee createEmployee(int id, String name, long salary, byte[] pic) ;
}



File: EmployeeServiceRemote.java




import javax.ejb.Remote;

@Remote
public interface EmployeeServiceRemote{
  public Employee createEmployee(int id, String name, long salary, byte[] pic) ;
  
  public void doAction();
}



File: Employee.java

import static javax.persistence.FetchType.LAZY;

import java.io.Serializable;

import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Lob;
import javax.persistence.Table;

@Entity
//@Table(name="EMP", schema="HR")
@Table(name="EMP")
public class Employee implements Serializable {
  @Id
  @Column(name = "EMP_ID")
  private int id;
  @Column(name = "COMM")
  private String name;
  @Column(name = "SAL")
  private long salary;

  @Basic(fetch=LAZY)
  @Lob @Column(name="PIC")
  private byte[] picture;
  
  public Employee() {
  }

  public Employee(int id) {
    this.id = id;
  }

  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }

  public long getSalary() {
    return salary;
  }

  public void setSalary(long salary) {
    this.salary = salary;
  }

  public byte[] getPicture() {
    return picture;
  }

  public void setPicture(byte[] picture) {
    this.picture = picture;
  }

  public String toString() {
    return "Employee id: " + getId() + " name: " + getName() + " salary: " + getSalary();
  }
}


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.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.createEmployee(158, "AAA", 45000, "asdf".getBytes());
    service.doAction();
  }

}


File: persistence.xml

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="EmployeeService" > <!-- transaction-type="JTA" -->
        <jta-data-source>java:/DefaultDS</jta-data-source>
        <properties>
         <property name="hibernate.hbm2ddl.auto" value="create-drop"/>
         <property name="hibernate.show_sql" value="true"/>
        </properties>
<!--
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
-->    
  </persistence-unit>
</persistence>




           
       








EJB-UsePersistenceContextToLinkToPersistenceContext.zip( 4,491 k)

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