JTable-TableModel

Question

class MyTableModel extends AbstractTableModel
final String columnNames[] = {
"Name", "Value"
String tableData[][];
public MyTableModel()
tableData = new String[1][2];
tableData[0][0] = new String("");
tableData[0][1] = new String("");
public Class getColumnClass(int i)
return getValueAt(0, i).getClass();
public int getColumnCount()
return columnNames.length;
public String getColumnName(int i)
return columnNames;
public int getRowCount()
return tableData.length;
public Object getValueAt(int i, int j)
return tableData[i][j];
public void setValueAt(String value, int row, int col) {
tableData[row][col] = value;
fireTableCellUpdated(row, col);
public boolean isCellEditable(int i, int j)
return true;
myModel=new MyTableModel();
table = new JTable(1,2);
table.setModel(myModel);
JScrollPane tablepane = new JScrollPane(table);
container.add(tablepane);
I want all cells in my table to be editable, and I think I've done everything that is necessary, but somehow it doesn't work. Initially all cells are empty. After I type on a cell and press enter or tab to change to other cell, the cell becomes empty again, the word I type disappears. What could be the problem & how to solve it? Thx.

Answer 1

This looks incorrect.
public Object getValueAt(int i, int j)
return tableData[j];
The object you are returning from getValueAt method is an Array.
Try this:
public Object getValueAt(int i, int j)
return tableData[ i ] [ j ];
Also (this is probably the one that's causing the problems) the
setValueAt() method is not overriding the method you think it
is. The method signature is incorrect. Change this:
public void setValueAt(String value, int row, int col)
tableData[row][col] = value;
fireTableCellUpdated(row, col);
to this:
public void setValueAt(Object value, int row, int col)
if ( value !=null )
tableData[row][col] = value.toString();
I don't think you need the fireTableCellUpdated() method call.
And one more thing (this is just a performance improvement).
You can remove the getColumnClass() method. The implementation
on AbstractTableModel will do the same thing, and it will
do it faster.
later
jc