public void setAlignment (int alignment) {
	checkWidget ();
	if ((alignment & (SWT.LEFT | SWT.RIGHT | SWT.CENTER)) == 0) return;
	int index = getIndex ();
	if (index == -1 || index == 0) return;	/* column 0 can only have left-alignment */
	alignment = CTable.checkBits (alignment, SWT.LEFT, SWT.CENTER, SWT.RIGHT, 0, 0, 0);
	int style = getStyle ();
	if ((style & alignment) != 0) return;	/* same value */
	style &= ~(SWT.LEFT | SWT.CENTER | SWT.RIGHT);
	style |= alignment;
	setStyle (style);
	int x = getX ();
	parent.redraw (x, 0, width, parent.clientArea.height, false);
	if (parent.drawCount <= 0 && parent.getHeaderVisible ()) {
		/* don't damage the header's drawn borders */
		parent.header.redraw (x, 1, width - 2, parent.getHeaderHeight () - 3, false);
	}
}