org.apache.hadoop.hbase
Class MasterAddressTracker
java.lang.Object
org.apache.hadoop.hbase.zookeeper.ZooKeeperListener
org.apache.hadoop.hbase.zookeeper.ZooKeeperNodeTracker
org.apache.hadoop.hbase.MasterAddressTracker
public class MasterAddressTracker
- extends ZooKeeperNodeTracker
Manages the location of the current active Master for this RegionServer.
Listens for ZooKeeper events related to the master address. The node
/master
will contain the address of the current master.
This listener is interested in
NodeDeleted
and NodeCreated
events on
/master
.
Utilizes ZooKeeperNodeTracker
for zk interactions.
You can get the current master via getMasterAddress()
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
MasterAddressTracker
public MasterAddressTracker(ZooKeeperWatcher watcher,
Abortable abortable)
- Construct a master address listener with the specified
zookeeper
reference.
This constructor does not trigger any actions, you must call methods
explicitly. Normally you will just want to execute ZooKeeperNodeTracker.start()
to
begin tracking of the master address.
- Parameters:
watcher
- zk reference and watcherabortable
- abortable in case of fatal error
getMasterAddress
public ServerName getMasterAddress()
- Get the address of the current master if one is available. Returns null
if no current master.
- Returns:
- Server name or null if timed out.
hasMaster
public boolean hasMaster()
- Check if there is a master available.
- Returns:
- true if there is a master set, false if not.
Copyright © 2014 The Apache Software Foundation. All Rights Reserved.