Update a JTable with setValueAt

Question

I have a JTable that is created from an AbstractTableModel. I am successfully initialising the table on the screen. (it is an informational table only - clicks are disabled) When i call setValueAt from the JTable object nothing happens.

Any help is much appreciated! Thanks in advance.

public void initialiseAuxDataStructure(TableModel table) {
    JTable auxDS = new JTable(table);
    Font f = auxDS.getFont();
    auxDS.setFont(new Font(f.getFontName(), f.getStyle(), f.getSize()+2));
    auxDS.setFocusable(false);
    auxDS.setRowSelectionAllowed(false);

    JTableHeader header = auxDS.getTableHeader();
    f = header.getFont();
    header.setFont(new Font(f.getFontName(), Font.BOLD, f.getSize()+2));

    pnlCenter.add(new JScrollPane(auxDS), BorderLayout.CENTER);
    pnlCenter.revalidate();

}

public void updateTable(String value, int row, int col) {
    auxDS.setValueAt(value, row, col);
    auxDS.revalidate();
}

and the abstract table model is:

public class TableModel extends AbstractTableModel {

private String[] columnNames;
private Object[][] data;

public TableModel(String[] columnNames, int columns) {
    this.columnNames = columnNames;
    data = new Object[columns][columnNames.length];
    for (int i=0; i<columns;i++) {
        data[i][0] = i;
    }
}

public TableModel(String[] colNames, Object[][] startData){
    this.columnNames = colNames;
    this.data = startData;
}

public int getColumnCount() {
    return columnNames.length;
}

public int getRowCount() {
    return data.length;
}

public String getColumnName(int col) {
    return columnNames[col];
}

public Object getValueAt(int row, int col) {
    return data[row][col];
}

}

all the cells are created in the model so i never want to change the structure of the table, just the values in it — Josh
No need to add a comment. Update your original posting so all the information is in one place. You posted the same code twice so we have no idea how you extend the AbstractTableModel. By default the setValueAt() method is not implemented. I suggest you just use the DefaultTableModel so you don't have to write your own code to implement the table model. — camickr
Also, you shouldn't be calling setValueAt on the JTable object; call it on the table's model instead (remember that the JTable can display data in a different order than what is stored in the model). — BenCole
@BenCole, There is not problem calling setValueAt() on the JTable. It depends on your requiremnt. If you want to update values based on the view (ie. maybe the table is sorted) then you use the table method. — camickr

camickr camickr · Accepted Answer · 2011-12-02T16:33:21

I gave you the answer in my comment.

You didn't implement the setValueAt() method so nothing happens.

You can read the JTable API and follow the link to the Swing tutorial on How to Use Tables where you will find a simple implementation.

Or you can use the DefaultTableModel which already does this for you.

Update a JTable with setValueAt

1 Answers