jTable add multiple row

Question

I'm trying to add multiple rows to a JTable. I've got jTable1 and want to add some results to jTable2. Here is my code:

DefaultTableModel model = new DefaultTableModel();
private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {
    model.addColumn("id");
    model.addColumn("miestas");
    model.addColumn("adresas");
    model.addColumn("pavadinimas");
    model.addColumn("kaina");
    model.addColumn("kiekis");
    model.addColumn("data");
    int i=jTable1.getSelectedRow();
    DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
    jXDatePicker1.setFormats(dateFormat);
    String date = dateFormat.format(jXDatePicker1.getDate()).toString();
    String c1=jTable1.getValueAt(i, 0).toString();
    String c2=jTable1.getValueAt(i, 1).toString();
    String c3=jTable1.getValueAt(i, 2).toString();
    String c4=jTable1.getValueAt(i, 3).toString();
    String c5=price.getText().toString();
    String c6=jTextField1.getText().toString();
    String c7=date;
    model.addRow(new Object[]{c1, c2, c3, c4, c5, c6, c7});
    jTable2.setModel(model);
}

The first row would add just fine, but when I add the second one it also add blank columns on right side, the mode rows I try to add it would add 7 blank columns on side.

Answer 1

That is because you keep adding columns to the model

model.addColumn("id");
model.addColumn("miestas");
model.addColumn("adresas");
model.addColumn("pavadinimas");
model.addColumn("kaina");
model.addColumn("kiekis");
model.addColumn("data");

Repeats each time you call the method

Answer 2

You can do this

public class ClassName {

    String[] columns = {"ID", "miestas", "adresas", "pavadinimas", "kaina", "kiekis", "data"};

    DefaultTableModel model;

    public ClassName() {

        model = new DefaultTableModel(columns, 0); //sets columns and number of rows once
    }

    private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {
        int i = jTable1.getSelectedRow();
        DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
        jXDatePicker1.setFormats(dateFormat);
        String date = dateFormat.format(jXDatePicker1.getDate()).toString();
        String c1 = jTable1.getValueAt(i, 0).toString();
        String c2 = jTable1.getValueAt(i, 1).toString();
        String c3 = jTable1.getValueAt(i, 2).toString();
        String c4 = jTable1.getValueAt(i, 3).toString();
        String c5 = price.getText().toString();
        String c6 = jTextField1.getText().toString();
        String c7 = date;
        model.addRow(new Object[]{c1, c2, c3, c4, c5, c6, c7});
        jTable2.setModel(model);
    }
}