/** Ping the jedis instance, return true if the result is PONG. */
private boolean ping(ConnectionInfo connectionInfo) {
Jedis jedis = new Jedis(connectionInfo.getHost(), connectionInfo.getPort());
try {
String result = jedis.ping();
return (result != null) && result.equals("PONG");
} catch (JedisException e) {
return false;
} finally {
JedisUtils.closeJedis(jedis);
}
}
/** Interrupt the thread and stop the blocking subscription. */
private void shutdown() {
running.getAndSet(false);
this.interrupt();
try {
if (subscriber != null) {
subscriber.unsubscribe();
}
} finally {
JedisUtils.closeJedis(sentinelJedis);
}
}
@Override
public void run() {
while (running.get()) {
try {
boolean avalibleSentinelExist = selectSentinel();
if (avalibleSentinelExist) {
try {
ConnectionInfo masterConnectionInfo = queryMasterAddress();
if ((internalPool != null) && isMasterAddressChanged(masterConnectionInfo)) {
logger.info(
"The internalPool {} had changed, destroy it now.",
previousMasterConnectionInfo.getHostAndPort());
destroyInternalPool();
}
if ((internalPool == null) || isMasterAddressChanged(masterConnectionInfo)) {
logger.info(
"The internalPool {} is not init or the address had changed, init it now.",
masterConnectionInfo.getHostAndPort());
initInternalPool(masterConnectionInfo);
}
previousMasterConnectionInfo = masterConnectionInfo;
// blocking listen master switch message until exception happen.
subscriber = new MasterSwitchSubscriber();
sentinelJedis.subscribe(subscriber, "+switch-master", "+redirect-to-master");
} catch (JedisConnectionException e) {
JedisUtils.closeJedis(sentinelJedis);
if (running.get()) {
logger.error(
"Lost connection with Sentinel "
+ sentinelInfo.getHostAndPort()
+ ", sleep 1000ms and try to connect another one.");
sleep(RETRY_WAIT_TIME_MILLS);
}
} catch (Exception e) {
JedisUtils.closeJedis(sentinelJedis);
if (running.get()) {
logger.error(
"Unexpected Exception happen, current Sentinel is"
+ sentinelInfo.getHostAndPort()
+ ", sleep 1000ms and try again.",
e);
sleep(RETRY_WAIT_TIME_MILLS);
}
}
} else {
logger.info("All sentinels down, sleep 1000ms and try to select again.");
// when the system startup but the sentinels not yet, init an ugly address to prevent
// null point
// exception.
if (internalPool == null) {
ConnectionInfo masterConnectionInfo = new ConnectionInfo(UNAVAILABLE_MASTER_ADDRESS);
initInternalPool(masterConnectionInfo);
previousMasterConnectionInfo = masterConnectionInfo;
}
sleep(RETRY_WAIT_TIME_MILLS);
}
} catch (Exception e) {
logger.error("Unexpected exception happen", e);
sleep(RETRY_WAIT_TIME_MILLS);
}
}
}