Saving Objects from an Iterated List

Question

I'm currently workin' on a sales module using java+hibernate+oracle... I'm done with my order form in my jsp like this:

I'm getting my parameters doing this:

ArrayList<String> idMercaderias = new ArrayList<String>();
ArrayList<String> cantidades = new ArrayList<String>();
ArrayList<String> precios = new ArrayList<String>();
for (int k = 0; k < 10; k++) {
  idMercaderias.add(request.getParameter("idMercaderia" + k));
  cantidades.add(request.getParameter("cantidad" + k));
  precios.add(request.getParameter("precio" + k));
}

I have 10 rows on my order detail, so I made the for, where my inputs are input1, input2, input3, etc. These are attributes of my object Mercaderia so i need to set them up, since they're on lists:

First I'm filtering the first list to avoid repeated articles:

Iterator itra = idMercaderias.listIterator();
ArrayList<String> sortedListIdMercaderias = new ArrayList<String>();
Object m;
while (itra.hasNext()) {
m = itra.next();
  if (!sortedListIdMercaderias.contains(m)) {
  sortedListIdMercaderias.add((String) m);
  }
}

Now I create my object to set all the attributes:

DetallePedido detalle = new DetallePedido();

Now I'm doing a cycle 10 times (thinking of all rows in my form) and start to iterate each list to get my object attributes avoiding null or empty entries.

for (int x = 0; x < sortedListIdMercaderias.size(); x++) {
Iterator itr = idMercaderias.listIterator();
while (itr.hasNext()) {
  String mercaderia = (String) itr.next();
  if ((mercaderia != null) && (!mercaderia.equals(""))) {
    Mercaderia mercaderiaSeleccionada = new MercaderiaDAO().findById(Integer.parseInt(mercaderia));
    detalle.setMercaderia(mercaderiaSeleccionada);
    }
}

Iterator itr2 = cantidades.listIterator();
while (itr2.hasNext()) {
  String cantidad = (String) itr2.next();
  if ((cantidad != null) && (!cantidad.equals(""))) {
    int cantidadMercaderiaSeleccionada = Integer.parseInt(cantidad);
    detalle.setCantidad(cantidadMercaderiaSeleccionada);
    }
}

Iterator itr3 = precios.listIterator();
while (itr3.hasNext()) {
  String precio = (String) itr3.next();
  if ((precio != null) && (!precio.equals(""))) {
    BigDecimal precioMercaderiaSeleccionada = new BigDecimal(precio);
    detalle.setPrecioUnitario(precioMercaderiaSeleccionada);                    
    }
}

Finally i just persist to my database:

Session session = new DetallePedidoDAO().getSession();
Transaction tx = session.beginTransaction();
try {
  session.saveOrUpdate(detalle);
  tx.commit();
session.close();
} catch (HibernateException e) {
  // TODO Auto-generated catch block
  e.printStackTrace();
}
}

I don't know why in the database i only get 1 row inserted (the last one with valid data) instead of all of them.

Any help will be really apreciated, this is for my final test in university project.

Answer 1

So, following the clues by David Wallace I made some tweaks to the idea and created an object WrapperDetallePedido like this:

public class WrapperDetallePedido {

    int idMercaderia;
    int cantidad;
    double precio;

    public int getIdMercaderia() {
        return idMercaderia;
    }
    public void setIdMercaderia(int idMercaderia) {
        this.idMercaderia = idMercaderia;
    }
    public int getCantidad() {
        return cantidad;
    }
    public void setCantidad(int cantidad) {
        this.cantidad = cantidad;
    }
    public double getPrecio() {
        return precio;
    }
    public void setPrecio(double precio) {
        this.precio = precio;
    }

}

Then in my Controller I created a single ArrayList and set my DetallePedido attributes:

ArrayList<WrapperDetallePedido> listado = new ArrayList<WrapperDetallePedido>();
for (int k = 0; k < 10; k++) {
        if (!request.getParameter("idMercaderia" + k).equals("")){
            WrapperDetallePedido WDetallePedido = new WrapperDetallePedido();
            WDetallePedido.setIdMercaderia(Integer.parseInt(request.getParameter("idMercaderia" + k)));
            WDetallePedido.setCantidad(Integer.parseInt(request.getParameter("cantidad" + k)));
            WDetallePedido.setPrecio(Double.parseDouble(request.getParameter("precio" + k)));
            listado.add(WDetallePedido);
        }                   
    }

Finally used Iterator for the previous list and set all the items from listado and persist to the database:

for (Iterator iterador = listado.listIterator(); iterador.hasNext();) {
    WrapperDetallePedido detalle = (WrapperDetallePedido) iterador.next();
    Mercaderia mercaderiaSeleccionada = new MercaderiaDAO().findById(detalle.getIdMercaderia());
    DetallePedido detallePedido = new DetallePedido();
    detallePedido.setMercaderia(mercaderiaSeleccionada);
    detallePedido.setCantidad(detalle.getCantidad());
    detallePedido.setPrecioUnitario(new BigDecimal(detalle.getPrecio()));
    detallePedido.setPedidos(pedidoGenerado);
    Session session1 = new DetallePedidoDAO().getSession();
    Transaction tx1 = session1.beginTransaction();
    new DetallePedidoDAO().save(detallePedido);
    try {
        session1.saveOrUpdate(detallePedido);
        tx1.commit();
        session1.close();
        } catch (HibernateException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

Finally got all my rows inserted as i needed... Thank you!

Answer 2

You've only ever got one DetallePedido object. You're changing its field values over and over in the various loops, but it's still just one object. Lastly you're saving it. Just once. Naturally, you only get one row inserted in your database.

What you could try is, instead of iterating through your Mercaderia objects, your Cantidad objects and your Precio objects separately; have a single loop that WITHIN EACH ITERATION creates a new DetallePedido object, sets the Mercaderia, the Cantidada and the Precio, and then saves the DetallePedido.