@Override
public void onDown(Host host) {
// Note that with well behaved balancing policy (that ignore dead nodes), the removePool call
// is not necessary
// since updateCreatedPools should take care of it. But better protect against non well
// behaving policies.
removePool(host);
updateCreatedPools();
}
/*
* When the set of live nodes change, the loadbalancer will change his
* mind on host distances. It might change it on the node that came/left
* but also on other nodes (for instance, if a node dies, another
* previously ignored node may be now considered).
*
* This method ensures that all hosts for which a pool should exist
* have one, and hosts that shouldn't don't.
*/
private void updateCreatedPools() {
for (Host h : cluster.getMetadata().allHosts()) {
HostDistance dist = loadBalancingPolicy().distance(h);
HostConnectionPool pool = pools.get(h);
if (pool == null) {
if (dist != HostDistance.IGNORED && h.getMonitor().isUp()) addOrRenewPool(h);
} else if (dist != pool.hostDistance) {
if (dist == HostDistance.IGNORED) {
removePool(h);
} else {
pool.hostDistance = dist;
}
}
}
}
@Override
public void onRemove(Host host) {
removePool(host);
updateCreatedPools();
}