At times, the width of a table column is so constrained that it obscures the data. Sometimes, the data is obscured because data itself too large for the cell. To alleviate this problem, you can use a MouseMotionListener to tap the mouse motion event and display the necessary data. So when the user brings the mouse cursor over a cell, the data in that cell is taken and displayed as a tooltip.

The following code sets the tooltip for the second column in a table. If the mouse cursor is moved over any other column, the tooltip is not displayed at all.

table.addMouseMotionListener(new MouseMotionAdapter() {    public void mouseMoved(MouseEvent me) {	int iRow = table.rowAtPoint(me.getPoint());	int iCol = table.columnAtPoint(me.getPoint());	if((iRow < 0) || (iCol < 0))	    return;	String toolTip = (String)table.getValueAt(iRow,iCol);	if(iCol == 2) {	    table.setToolTipText(toolTip);	} else {	    toolTip = null;	    table.setToolTipText(toolTip);	}    }});

Some values, like the Column number have been hard-coded in the interest of brevity.