public SelectNode apply(SelectNode sn) {
// do a deep copy of the existing query SelectNode before
// modifying it:
SelectNode newSelectNode = sn.deepCopy();
for (AxisNode an : newSelectNode.getAxisList()) {
if (an.getAxis() == axis) {
// this is the axis we're drilling
ParseTreeNode initialAxisExp = an.getExpression();
// apply the drill operation
ParseTreeNode newAxisExp = processAxisExp(initialAxisExp);
// replace the expression in the axis by the new generated one
an.setExpression(newAxisExp);
}
}
return newSelectNode;
}
