check if entity is change

[szaccaria]

Hi to all,
It is possible to know if a entity it is changed after submit a form and first the entityManager flush this change in db? I make this kind of question because I need to controll if a entity be changed from the user, so I can sign a flag.

Morover I have the follow SFSB

@Stateful
@Scope(ScopeType.CONVERSATION)
@Name("gestione")
public class Gestione implements GestioneI {

 @PersistenceContext(type = PersistenceContextType.EXTENDED)
 EntityManager entityManager;

 @Out(scope = ScopeType.CONVERSATION, required = false)
 Documento doc;

 @In(required = false)
 Long idDocumento;

 @In(required = false)
 TaskInstance taskInstance;

 @In
 private Actor actor;

 @Logger
 private Log log;

 @DataModel
 private List<TaskInstance> taskInstacesResponsabile;

 @DataModelSelection
 private TaskInstance task;

 private String tab;

 @StartTask(flushMode=FlushModeType.MANUAL)
 public String iniziaValutazioneDoc(String tab) {

 String out = continuaValutazioneDoc(tab);

 return out;
 }

 @BeginTask(flushMode=FlushModeType.MANUAL)
 public String continuaValutazioneDoc(String tab) {

 this.tab = tab;

 doc = (Documento) entityManager.createQuery("select distinct d from Documento d where d.id = :id").setParameter("id", idDocumento).getSingleResult();

 return "/documento.xhtml";

 }

 @BeginTask
 @EndTask(transition = "confermato")
 public String chiudiValutazioneDoc(String tab) {

 if (taskInstance.getStart() == null)
 taskInstance.start();

 this.tab = tab;

 return "/todo2.xhtml";
 }

 @EndTask(transition = "confermato")
 public String confermaAInterno(String tab) {

 taskInstance.setActorId((String)taskInstance.getVariable("responsabile"));

 taskInstance.setVariable(getTrackVariableNameForActor(actor), actor.getId());


 this.tab = tab;

 return "/todo.xhtml";
 }

 @End
 public String sospendiValutazioneDoc(String tab) {

 this.tab = tab;
 return "/todo2.xhtml";

 }





 @Destroy
 @Remove
 public void destroy() {
 }



 public void caricaTasksInCarico() {

 JbpmContext context = ManagedJbpmContext.instance();

 taskInstacesResponsabile = context.getSession().createQuery(
 "select ti "+
 "from org.jbpm.taskmgmt.exe.TaskInstance ti, "+
 " org.jbpm.context.exe.VariableInstance vi join vi.processInstance pi " +
 "where " +
 " pi.end = null and " +
 " ti.token.processInstance = pi and " +
 " vi.name = :track and " +
 " vi.value = :trackValue and " +
 " ( ti.actorId = null or ti.actorId != :actorId ) and " +
 " ti.isOpen = true" ).setString("track", getTrackVariableNameForActor(actor)).setString("trackValue",actor.getId()).setString("actorId", actor.getId()).list();


 for (Iterator iter = taskInstacesResponsabile.iterator(); iter.hasNext();) {
 TaskInstance element = (TaskInstance) iter.next();
 log.error("TaskInstance n° #0 di #1", element.getId(), element.getActorId());
 }

 }

 /**
 * Genero il documento pdf in memoria
 */
 public String stampaDocumento() {

 FacesContext faces = FacesContext.getCurrentInstance();

 ByteArrayOutputStream bAOS = PdfUtility.stampaPDF(doc);

 HttpServletResponse response = (HttpServletResponse) faces.getExternalContext().getResponse();
 response.setContentType("application/pdf");
 response.setContentLength(bAOS.size());
 response.setHeader("Content-disposition", "Attachment; filename=\"" + doc.getClifor() + "_" + doc.getNumdoc() + ".pdf" + "\"");
 try {
 ServletOutputStream out;
 out = response.getOutputStream();
 out.write(bAOS.toByteArray());
 } catch (IOException e) {
 e.printStackTrace();
 }
 faces.responseComplete();

 return null;

 }


 public String consultazioneDocumento( String tab) {

 doc = (Documento) entityManager.createQuery("select distinct d from Documento d where d.id = :id").setParameter("id", task.getVariable("idDocumento"))
 .getSingleResult();

 this.tab = tab;
 return "/documento.xhtml";

 }



 public String salvaDocumento() {

 entityManager.persist(doc);

 return null;
 }

 public TaskInstance getTaskInstance() {
 return taskInstance;
 }

 public void setTaskInstance(TaskInstance taskInstance) {
 this.taskInstance = taskInstance;
 }

 /**
 * Mi torna il nome della variabile track per l'utente actor
 */
 private String getTrackVariableNameForActor(Actor actor) {

 String sActor = actor.getId();
 StringBuffer trackBuff = new StringBuffer();
 trackBuff.append("trackFor");
 if (sActor != null && sActor.trim().length() > 1) {
 trackBuff.append(sActor.substring(0, 1).toUpperCase());
 trackBuff.append(sActor.substring(1));
 }
 return trackBuff.toString();

 }


}

when I call from a xhtml page the action: gestione.stampaDocumento
like:

<h:form>
<h:commandButton
 action="#{gestione.stampaDocumento}"
 value="#{messages.generapdf}"
 style="border: none;"
 image="/img/pdf.png"
 title="#{messages.generapdf}"
 rendered="#{s:hasRole('controllo')}">
</h:commandButton>
</h:form>

The possible change that user made to the endity are flush in to the db, although i don't end the conversation, ( flushMode=FlushModeType.MANUAL is set in al @starttask )

Thanks !!!