adding sum column on jtable that is binded to a database table

Hi all,

I hope this is the correct thread to make this post.
I have a database application created with NetBeans very similar to this one:
Creating a Custom Java Desktop Database Application - NetBeans 6.5 Tutorial

I would like to add another column on the customer (master) table that will display the sum of the orders cost that each customer has done.

I dont think I need to create another column on the database table to hold that value. I tried to create a new property on the Customer entity but it requires that this property exists in the database table as well so I removed the new property.

I also tried to change the query to
SELECT c, SUM(c.orders.price) From Customer c
and then map the sum to the appropriate column but also didnt work.

Any ideas on how I could make this work?

Thank you
GK

My guess is that you'll need to change the TableModel for the JTable to have one more column and then override the table model's getValueAt method to display a sum of data from the row. What kind of TableModel are you currently using?

Thanks for the quick reply.

I m using the autogenerated table model. I believe its the default one. This is the code for the customerTable:

Code:

---

customerTable.setName("customerTable"); // NOI18N

        org.jdesktop.swingbinding.JTableBinding jTableBinding = org.jdesktop.swingbinding.SwingBindings.createJTableBinding(org.jdesktop.beansbinding.AutoBinding.UpdateStrategy.READ_WRITE, list, customerTable);
        org.jdesktop.swingbinding.JTableBinding.ColumnBinding columnBinding = jTableBinding.addColumnBinding(org.jdesktop.beansbinding.ELProperty.create("${custSurname}"));
        columnBinding.setColumnName("Cust Surname");
        columnBinding.setColumnClass(String.class);
        columnBinding.setEditable(false);
        columnBinding = jTableBinding.addColumnBinding(org.jdesktop.beansbinding.ELProperty.create("${custName}"));
        columnBinding.setColumnName("Cust Name");
        columnBinding.setColumnClass(String.class);
        columnBinding.setEditable(false);
        columnBinding = jTableBinding.addColumnBinding(org.jdesktop.beansbinding.ELProperty.create("${custTel}"));
        columnBinding.setColumnName("Cust Tel");
        columnBinding.setColumnClass(String.class);
        columnBinding.setEditable(false);
        columnBinding = jTableBinding.addColumnBinding(org.jdesktop.beansbinding.ELProperty.create("${custAddr}"));
        columnBinding.setColumnName("Cust Addr");
        columnBinding.setColumnClass(String.class);
        columnBinding.setEditable(false);
        columnBinding = jTableBinding.addColumnBinding(org.jdesktop.beansbinding.ELProperty.create("${comments}"));
        columnBinding.setColumnName("Comments");
        columnBinding.setColumnClass(String.class);
        columnBinding.setEditable(false);
        columnBinding = jTableBinding.addColumnBinding(org.jdesktop.beansbinding.ObjectProperty.create());
        columnBinding.setEditable(false);
        bindingGroup.addBinding(jTableBinding);
        jTableBinding.bind();

---

I can add a column but I m not sure how the binding can be done. I was thinking something like:

jTableBinding.addColumnBinding(org.jdesktop.beansb inding.ELProperty.create("${customer.orders.price} "));

but it is not allowed by netbeans and its not working since it also needs to get a sum function in there somehow.

I also have created a query that returns the customers with the total price of each ones orders but I dont think this is how it will work since the data is binded directly to the table.

:confused:

Thanks,
GK

You should try adding a transient field in customer entity class and setting sum value to it.

Yeap, that did the trick.

Thanks!!!! :D