public void onUp(Host host) {
HostConnectionPool previous = addHost(host);
;
loadBalancer.onUp(host);
// This should not be necessary but it's harmless
if (previous != null) previous.shutdown();
}
private boolean shutdown(long timeout, TimeUnit unit) throws InterruptedException {
if (!isShutdown.compareAndSet(false, true)) return true;
long start = System.nanoTime();
boolean success = true;
for (HostConnectionPool pool : pools.values())
success &= pool.shutdown(timeout - Cluster.timeSince(start, unit), unit);
return success;
}
public void onAdd(Host host) {
HostConnectionPool previous = addHost(host);
;
loadBalancer.onAdd(host);
// This should not be necessary, especially since the host is
// supposed to be new, but it's safer to make that work correctly
// if the even is triggered multiple times.
if (previous != null) previous.shutdown();
}
/*
* 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;
}
}
}
}
public void onDown(Host host) {
loadBalancer.onDown(host);
HostConnectionPool pool = pools.remove(host);
// This should not be necessary but it's harmless
if (pool != null) pool.shutdown();
// If we've remove a host, the loadBalancer is allowed to change his mind on host distances.
for (Host h : cluster.getMetadata().allHosts()) {
if (!h.getMonitor().isUp()) continue;
HostDistance dist = loadBalancer.distance(h);
if (dist != HostDistance.IGNORED) {
HostConnectionPool p = pools.get(h);
if (p == null) addHost(host);
else p.hostDistance = dist;
}
}
}
private void removePool(Host host) {
HostConnectionPool pool = pools.remove(host);
if (pool != null) pool.shutdown();
}
public void onRemove(Host host) {
loadBalancer.onRemove(host);
HostConnectionPool pool = pools.remove(host);
if (pool != null) pool.shutdown();
}
private void shutdown() {
if (!isShutdown.compareAndSet(false, true)) return;
for (HostConnectionPool pool : pools.values()) pool.shutdown();
}