public HostConnectionPool(Host host, HostDistance hostDistance, Session.Manager manager)
throws ConnectionException {
assert hostDistance != HostDistance.IGNORED;
this.host = host;
this.hostDistance = hostDistance;
this.manager = manager;
this.newConnectionTask =
new Runnable() {
@Override
public void run() {
addConnectionIfUnderMaximum();
scheduledForCreation.decrementAndGet();
}
};
// Create initial core connections
List<Connection> l =
new ArrayList<Connection>(options().getCoreConnectionsPerHost(hostDistance));
try {
for (int i = 0; i < options().getCoreConnectionsPerHost(hostDistance); i++)
l.add(manager.connectionFactory().open(host));
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
// If asked to interrupt, we can skip opening core connections, the pool will still work.
// But we ignore otherwise cause I'm not sure we can do much better currently.
}
this.connections = new CopyOnWriteArrayList<Connection>(l);
this.open = new AtomicInteger(connections.size());
logger.trace("Created connection pool to host {}", host);
}
private boolean addConnectionIfUnderMaximum() {
// First, make sure we don't cross the allowed limit of open connections
for (; ; ) {
int opened = open.get();
if (opened >= options().getMaxConnectionsPerHost(hostDistance)) return false;
if (open.compareAndSet(opened, opened + 1)) break;
}
if (isShutdown()) {
open.decrementAndGet();
return false;
}
// Now really open the connection
try {
connections.add(manager.connectionFactory().open(host));
signalAvailableConnection();
return true;
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
// Skip the open but ignore otherwise
open.decrementAndGet();
return false;
} catch (ConnectionException e) {
open.decrementAndGet();
logger.debug("Connection error to {} while creating additional connection", host);
if (host.getMonitor().signalConnectionFailure(e)) shutdown();
return false;
} catch (AuthenticationException e) {
// This shouldn't really happen in theory
open.decrementAndGet();
logger.error(
"Authentication error while creating additional connection (error is: {})",
e.getMessage());
shutdown();
return false;
}
}