Get total in a row cell in Java

Question

I create a demo above. JTable retrieves 'ID', 'Name' and 'Cost' from MySQL database. User can enter a quantity (Qty) and Discount price in 'Discount'.

I want to display total in'Total' when the user press the TAB key on keyboard to move into the next cell.

Total have to be (Cost*Qty)-Discount

How can I implement this?

I Found a Solution :

String sql = "select ItemID,ItemName,CostPrice from druginfo where ItemID=?";
    try {   
        pst=conn.prepareStatement(sql);
        pst.setString(1, temp);

        rs=pst.executeQuery();
        addDataToTable(tableSale,DbUtils.resultSetToTableModel(rs));

        IDcombo.setSelectedItem(null);
        Namecombo.setSelectedItem(null);
        exptxt.setText(null);
        instock.setText(null);

        //getting user input for selling qty 
        String Qty=JOptionPane.showInputDialog("Insert Selling Quantity :");
        double sellingqty=Double.parseDouble(Qty);
        //setting qty input value to table sale  
        tableSale.getModel().setValueAt(sellingqty,i, 3);

        //getting user input for specific item discount
        String discount = JOptionPane.showInputDialog("Insert Item Discount");
        double idiscount=Double.parseDouble(discount);
        //setting input value to table sale  
        tableSale.getModel().setValueAt(idiscount,i, 4);

        //getting item cost from the table sale 
        double icost =(double) tableSale.getModel().getValueAt(i,2); 

        //calculating Gross Total  
        double grosstotal = (sellingqty*icost)-idiscount;

        //setting grosstotal value to table sale
        tableSale.getModel().setValueAt(grosstotal,i, 5); 

        String invoice = InvoiceNo_txt.getText(); 
        String id = (String) tableSale.getValueAt(i, 0);
        String name = (String) tableSale.getValueAt(i, 1);
        double dcost =  (double) tableSale.getValueAt(i, 2);
        String cost = String.valueOf(dcost);//converting double to string
        double dqty = (double) tableSale.getValueAt(i, 3);
        String qty = String.valueOf(dqty);//converting double to string
        double ditemDiscount = (double) tableSale.getValueAt(i, 4);
        String itemDiscount = String.valueOf(ditemDiscount);//converting double to string
        double dgrossTotal = (double) tableSale.getValueAt(i, 5);
        String grossTotal = String.valueOf(dgrossTotal);//converting double to string

Answer 1

Take a look here how they override TableModelListener#tableChanged method. If you can not find a solution for tab then check it tableChanged event handler does the same job, inside the method probably you will set a new value in total cell.

Answer 2

You can try looking for a TableModelListener...Add it to your TableModel.In TableModelListener check for update cell and then check for column no which was updated.If Discount column is updated get the value of three columns you need calculate the value and put it the total column. You can refer here Try to do it its very simple or else if in a hurry.Checkout the below code

     table.getModel().addTableModelListener( new TableModelListener() {

        @Override
        public void tableChanged(TableModelEvent e) {
            if (e.getType() == TableModelEvent.UPDATE) {

                int row = e.getFirstRow();
                int column = e.getColumn();
                if (column == 4 ) {
                    TableModel model = table.getModel();

                   int cost =  (model.getValueAt(row, 2)==null)?0:((Integer)model.getValueAt(row, 2)).intValue();
                  int quantity =(model.getValueAt(row, 3)==null)?0: ((Integer) model.getValueAt(row, 3)).intValue();
                  int discount = (model.getValueAt(row, 4)==null)?0:((Integer) model.getValueAt(row, 4)).intValue();

                    Integer total = new Integer((quantity * price)-discount);
                    model.setValueAt(total, row, 5);
                }
            }
        }
    };