public static SNode reverseList(SNode n) {
SNode last = n;
SNode dummy = new SNode(0);
while (n != null) {
SNode newNode = new SNode(n.key);
newNode.next = dummy.next;
dummy.next = newNode;
n = n.next;
}
return dummy.next;
}
/**
* Creates or resets fields of a node. Called only from transfer where the node to push on stack
* is lazily created and reused when possible to help reduce intervals between reads and CASes
* of head and to avoid surges of garbage when CASes to push nodes fail due to contention.
*/
static SNode snode(SNode s, Object e, SNode next, int mode) {
if (s == null) s = new SNode(e);
s.mode = mode;
s.next = next;
return s;
}