How to hide and block the last line of a Jtable?

Question

It is possible to hide and lock the last line of a DefaulTableModel?

I have this difficulty and I am not able to solve it. If it is not at least possible to hide this line?

import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;

public class Main extends JFrame {
  DefaultTableModel model = new DefaultTableModel(new Object[][] {
       {"Jack","19","Masculino"}, {"Eddie","56","Masculino"}, {"Gina","34","Feminino"},
      {"Klaus","18","Masculino"}, {"Erika","20","Feminino"},  {"Roberto","29","Masculino"},{"Maria","30","Feminino"} },
      new Object[] { "Nome:", "Idade:", "Sexo:" });

  public Main() {
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JTable table = new JTable(model);
    getContentPane().add(new JScrollPane(table), BorderLayout.CENTER);
    pack();
  }

  public static void main(String arg[]) {
    new Main().setVisible(true);
  }
}

I’d like to hide the last line.

Answer 1

If by "block" you mean prevent the line data from being edited, simply overwrite the method isCellEditable of TableModel as follows:

DefaultTableModel model =  new DefaultTableModel(dados, colunas) {

    @Override
    public boolean isCellEditable(int row, int column) {
        return row < (getRowCount() - 1);
    }
}

table=new JTable(model);

This method returns a boolean for each cell (crossing row x column) of the table, stating whether or not the table’s data can be edited. The above logic will return true while the line’s Dice is smaller than the last line.

But it doesn’t make much sense to block a line if you don’t even want to display it. The above method already prevents it from being changed by the user.

The example presented is also very generic, it does not present a problem to be solved. If you want to hide a row, the least complicated way is to remove it in the table with the method removeRow(), passing your index.

---

If you still want to insist on hiding the line while already blocked, is possible if the table already has a Tablerowsorter and you create a RowFilter that shows the rows to be displayed in the table, so that when it is the last one, it does not display:

RowFilter<TableModel, Integer> filter = new RowFilter<TableModel, Integer>(){

    @Override
    public boolean include(javax.swing.RowFilter.Entry<? extends TableModel, ? extends Integer> entry) {
        int modelRow = entry.getIdentifier();
        return modelRow < (table.getRowCount() - 1);
    }
};

...

((TableRowSorter<?>)table.getRowSorter()).setRowFilter(filter);

The method include returns a boolean if a given entry can be displayed in the table, in this case I am returns true for all cases where the input from the TableModel is smaller than the last line. It continues to exist in the model, but is not displayed in the view.

In the Oracle tutorial on Jtable you can read more about how to create and apply filters and sort rows of tables.