@Override
public void run() {
if (null != listeners.get(ledgerId)) {
LOG.debug("Re-read ledger metadata for {}.", ledgerId);
readLedgerMetadata(ledgerId, this, AbstractZkLedgerManager.this);
} else {
LOG.debug("Ledger metadata listener for ledger {} is already removed.", ledgerId);
}
}
@Override
public void operationComplete(int rc, final LedgerMetadata result) {
if (BKException.Code.OK == rc) {
// reset the back off after a successful operation
currentZKEBackOff = ZK_CONNECT_BACKOFF_MS_MIN;
final Set<LedgerMetadataListener> listenerSet = listeners.get(ledgerId);
if (null != listenerSet) {
LOG.debug("Ledger metadata is changed for {} : {}.", ledgerId, result);
scheduler.submit(
new Runnable() {
@Override
public void run() {
for (LedgerMetadataListener listener : listenerSet) {
listener.onChanged(ledgerId, result);
}
}
});
}
} else if (BKException.Code.NoSuchLedgerExistsException == rc) {
// the ledger is removed, do nothing
Set<LedgerMetadataListener> listenerSet = listeners.remove(ledgerId);
if (null != listenerSet) {
LOG.debug(
"Removed ledger metadata listener set on ledger {} as its ledger is deleted : {}",
ledgerId,
listenerSet.size());
}
} else {
// Use constant backoff for all bookkeeper specific exceptions;
// for ZK exceptions, use exponential back off
int backOff = ZK_CONNECT_BACKOFF_MS_MIN;
if (BKException.Code.ZKException == rc) {
backOff = currentZKEBackOff;
// Double the backoff for the next retry up to the maximum allowed back off
currentZKEBackOff = Math.min(2 * currentZKEBackOff, ZK_CONNECT_BACKOFF_MS_MAX);
}
LOG.warn("Failed on read ledger metadata of ledger {} : {}", ledgerId, rc);
scheduler.schedule(this, backOff, TimeUnit.MILLISECONDS);
}
}