tooltip text erasing table on panel

My tooltip text erasing the panel. Also I am unable to display large text in multiple lines. I cannot use <html> tags as I am passing string to tooltip. Any help could be appreciated. Thanks in advance...

JTable table = new JTable(dfm)
{
    public String getToolTipText( MouseEvent e )
                {
                    int row = rowAtPoint( e.getPoint() );
                    int column = columnAtPoint( e.getPoint() );

                    String value = getValueAt(row, column).toString();
                    return value == null ? null : value;
                }
            };

Solution

For displaying table cell data in multiple lines one can use the code as follows:

public class MyRenderer extends JTextArea implements TableCellRenderer {

/**
 * 
 */
private static final long serialVersionUID = 1L;

public MyRenderer() {
    setLineWrap(true);
    setWrapStyleWord(true);
    setOpaque(true);
}

@Override
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus,
        int row, int column) {
    // TODO Auto-generated method stub
    setText(value.toString());//or something in value, like value.getNote()..
    if (isSelected) {
        setForeground(table.getSelectionForeground());
        setBackground(table.getSelectionBackground());
    } else {
        setForeground(table.getForeground());
        setBackground(table.getBackground());
    }
    setSize(table.getColumnModel().getColumn(column).getWidth(),
        getPreferredSize().height);
    if (table.getRowHeight(row) != getPreferredSize().height) {
        table.setRowHeight(row, getPreferredSize().height);
    }
    return this;
      }
}

and tooltip error is not resolved