0 Replies Latest reply on Jun 4, 2006 2:11 PM by Gozar Mig

    Problem with concurrence client

    Gozar Mig Newbie

      I all,
      i try to implement a sevice to booking a room.
      I must to deploiy it on jboss 3.2.7 and i use CMT

      The problem is when 2 client A, B call at same time booking method:
      1)A: call "booking" with big Collection, order by date, include booking for tomorrow
      2) A: call "verifyAvaibleBooking(bookingVO)" and nobody booking for tomorrow
      3) B: call "booking" with only booking for tomorrow
      A: continues to verifyAvaibleBooking
      4) B call "verifyAvaibleBooking(bookingVO)" and nobody booking for tomorrow and create a booking for tomorrow
      5) A: terminate to verifyAvaibleBooking and create booking

      At the end of this computation i have 2 booking for tomorrow on the same room!

      This is my bookingBean:

      /* @ejb.bean name="Booking" display-name="Name for Booking"
       * description="Description for Booking" jndi-name="ejb/Booking"
       * local-jndi-name = "ejb/BookingLocal" type="CMP" cmp-version="2.x"
       * view-type="local" primkey-field = "id"
       *
       */
      
      public abstract class BookingBean implements EntityBean {
      //every get method have this tag
       /**
       * Getter for CMP Field id
       *
       * @ejb.persistent-field
       * @ejb.interface-method view-type="local"
       *
       */
      set...();
      get...();
      }
      


      Now i have a Stateful antity bean to manage previews bean:
      **
       * @ejb.bean name="ManageBooking" display-name="Name for ManageBooking"
       * description="Description for ManageBooking"
       * jndi-name="ejb/ManageBooking" type="Stateful" view-type="both"
       *
       * @ejb.resource-ref res-ref-name="jdbc/DefaultDS"
       * res-type="javax.sql.Datasource"
       * res-auth="Container"
       *
       *@jboss.resource-ref res-ref-name="jdbc/DefaultDS"
       * jndi-name="java:/DefaultDS"
       *
       * @jboss.container-configuration name="Standard Stateful SessionBean"
       *
       * @ejb.ejb-ref ejb-name="Booking" view-type="local" ref-name="ejb/BookingLocal"
       *
       * @ejb.ejb-ref ejb-name="User" view-type="local" ref-name="ejb/UserLocal"
       *
       * @ejb.ejb-ref ejb-name="ClassRoom" view-type="local"
       * ref-name="ejb/ClassRoomLocal"
       *
       * @ejb.ejb-ref ejb-name="Privilege" view-type="local"
       * ref-name="ejb/PrivilegeLocal"
       *
       * @ejb.ejb-ref ejb-name="MyConstraint" view-type="local"
       * ref-name="ejb/MyConstraintLocal"
       *
       */
      public abstract class ManageBookingBean implements SessionBean{
      
       //Define some variable
      
       /**
       * Sets the session context
       * @param javax.ejb.SessionContext the new ctx value
       * @ejb.method setSessionContext
       **/
       public void setSessionContext(SessionContext ctx) throws EJBException,
       RemoteException {
       this.ctx = ctx;
       }
      
       /**
       * Unsets the session context
       * @param javax.ejb.SessionContext ctx value
       * @ejb.method unsetSessionContext
       */
       public void unsetSessionContext() {
       this.ctx=null;
       }
      
       /**
       * Default create method
       *
       * @throws CreateException
       * @ejb.create-method
       */
       public void ejbCreate() throws CreateException {
       try {
       userLocalHome = UserUtil.getLocalHome();
       classRoomLocalHome = ClassRoomUtil.getLocalHome();
       bookingLocalHome = BookingUtil.getLocalHome();
       constraintLocalHome = MyConstraintUtil.getLocalHome();
       } catch (NamingException e) {
       // TODO Auto-generated catch block
       e.printStackTrace();
       }
       }
      
      
      //There are some (not transaction) method
      
       /**
       * Business method
       *
       * @ejb.interface-method view-type = "remote"
       * @ejb.transaction type = "Required"
       */
       public String booking(Collection bookingVO) {
       .....
       }
      }
      


      This is a booking mathod:

       /**
       * Business method
       *
       * @ejb.interface-method view-type = "remote"
       * @ejb.transaction type = "Required"
       */
       public String booking(Collection bookingVO) {
       UserLocal userBean = null;
       ClassRoomLocal classRoomBean = null;
       Iterator iter;
      
       // Verifico la disponibilità
       Collection collBooking = verifyAvaibleBooking(bookingVO);
      
       if (collBooking.isEmpty()) {
       String tmp = computeConstraint(bookingVO);
       if (tmp.startsWith("Danied")) {
       return tmp;
       }
       iter = bookingVO.iterator();
       while (iter.hasNext()) {
       BookingValue booking = (BookingValue) iter.next();
       try {
       userBean = userLocalHome.findByPrimaryKey(booking.getUser()
       .getUserName());
       classRoomBean = classRoomLocalHome.findByPrimaryKey(booking
       .getClassRoom().getName());
       } catch (FinderException e1) {
       // TODO Auto-generated catch block
       e1.printStackTrace();
       }
       try {
       BookingLocal bookingBean = bookingLocalHome.create();
       bookingBean.setBookingValue(booking);
       bookingBean.setClassRoom(classRoomBean);
       bookingBean.setUser(userBean);
       } catch (CreateException e) {
       Costanti.debug("Errore nella creazione delle prenotazione");
       ctx.setRollbackOnly();
       }
       }
       } else {
       return Costanti.DANIED_BOOKING
       + "<br>Impossibile effettuare la prenotazione"
       + "<br>Ci sono altre prenotazioni negli stessi orari e nelle stesse aule";
       }
       return Costanti.OK_BOOKING + "<br>Prenotazione effettuata con successo";
       }
      
      


      How can I make to resolve this problem?
      I know that i can use UserTransaction but i'm know that CMT make this for me!
      Someone can say me because i have this problem?
      Thanks for your help everyone