/**
* Returns true if the specified notification is newer than the current one.
*
* @param response the notification
* @return true if the notification is new
*/
public synchronized boolean isNew(Response response) {
if (!response.getOptions().hasObserve()) {
// this is a final response, e.g., error or proactive cancellation
return true;
}
// Multiple responses with different notification numbers might
// arrive and be processed by different threads. We have to
// ensure that only the most fresh one is being delivered.
// We use the notation from the observe draft-08.
long T1 = getTimestamp();
long T2 = System.currentTimeMillis();
int V1 = getCurrent();
int V2 = response.getOptions().getObserve();
int notifMaxAge =
NetworkConfig.getStandard().getInt(NetworkConfigDefaults.NOTIFICATION_MAX_AGE);
if (V1 < V2 && V2 - V1 < 1 << 23 || V1 > V2 && V1 - V2 > 1 << 23 || T2 > T1 + notifMaxAge) {
setTimestamp(T2);
number.set(V2);
return true;
} else {
return false;
}
}
