Codice

//PERSISTENCE

<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_2_0.xsd" version="2.0">

    <persistence-unit name="corsoWebPersistence" transaction-type="RESOURCE_LOCAL">

	<jta-data-source>connessioneCorsoWeb</jta-data-source>

	<properties>
		<property name="openejb.jpa.auto-scan" value="true"/>
	</properties>

    </persistence-unit>

</persistence>


//PERSONA SERLVET
package it.corso.java.web;

import java.io.IOException;

import javax.ejb.EJB;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import it.corso.java.business.PersonaServiceBeanLocal;
import it.corso.java.data.Persona;

/**
 * Servlet implementation class Persona
 */
@WebServlet("/persona")
public class PersonaServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	//OVVIAMENTE CI SERVE UNA EJB QUINDI LA CREIAMO
	@EJB
	PersonaServiceBeanLocal personaService;

    public PersonaServlet() {
        super();
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

		//NEL REQUEST GET PARAMETER POSSIAM GIA CONTROLLARE SE E NULL , SE NO ASSOCIAMI ALLA VARIABILE METHOD CHE C STA SCRITT
		String method = request.getParameter("method") != null ? request.getParameter("method") : "";
		if (method.equals("add")) {
			Persona p = new Persona();
			p.setNome("MARIO");
			p.setCognome("ROSSI");
			p.setAnni(34);
			personaService.inserisci(p);

		} else {

		}


	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}

}



//PERSONASERVICEBEAN
package it.corso.java.business;

import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

import it.corso.java.data.Persona;

/**
 * Session Bean implementation class PersonaServiceBean
 */
@Stateless
public class PersonaServiceBean implements PersonaServiceBeanRemote, PersonaServiceBeanLocal {

	//QUA DEFINIZIAMO L'ENTITY MANAGER

	//COME UNITNAME PRENDIAMO IL NOME DA DENTRO PERSISTENCE.XML , E LO METTIAMO
	@PersistenceContext(unitName="corsoWebPersistence")
	EntityManager manager;



	public PersonaServiceBean() {

    }
    //METODI CRUD

    public void inserisci(Persona p) {
    	manager.persist(p);
    }

    public void aggiorna(Persona p) {

    }


    public void cancella(Persona p) {
    	manager.remove(p);
    }

    public Persona getPersonaById(Long id) {
    	return null;
    }
}