ReplicationTrackerZKImpl (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.replication.ReplicationStateZKBase
- - org.apache.hadoop.hbase.replication.ReplicationTrackerZKImpl

All Implemented Interfaces:

ReplicationTracker
```
@InterfaceAudience.Private
public class ReplicationTrackerZKImpl
extends ReplicationStateZKBase
implements ReplicationTracker
```
This class is a Zookeeper implementation of the ReplicationTracker interface. This class is responsible for handling replication events that are defined in the ReplicationListener interface.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`class`	`ReplicationTrackerZKImpl.OtherRegionServerWatcher` Watcher used to be notified of the other region server's death in the local cluster.
`class`	`ReplicationTrackerZKImpl.PeersWatcher` Watcher used to follow the creation and deletion of peer clusters.

Field Summary

Fields
Modifier and Type	Field and Description
`private List<ReplicationListener>`	`listeners`
`private static org.apache.commons.logging.Log`	`LOG`
`private ArrayList<String>`	`otherRegionServers`
`private ReplicationPeers`	`replicationPeers`
`private Stoppable`	`stopper`

Fields inherited from class org.apache.hadoop.hbase.replication.ReplicationStateZKBase
abortable, conf, DISABLED_ZNODE_BYTES, ENABLED_ZNODE_BYTES, ourClusterKey, peerStateNodeName, peersZNode, queuesZNode, replicationZNode, zookeeper

Constructor Summary

Constructors
Constructor and Description
`ReplicationTrackerZKImpl(ZooKeeperWatcher zookeeper, ReplicationPeers replicationPeers, org.apache.hadoop.conf.Configuration conf, Abortable abortable, Stoppable stopper)`

Method Summary

Methods
Modifier and Type	Method and Description
`List<String>`	`getListOfRegionServers()` Return a snapshot of the current region servers.
`private String`	`getPeersZNode()`
`private List<String>`	`getRegisteredRegionServers()` Get a list of all the other region servers in this cluster and set a watch
`private String`	`getZNodeName(String fullPath)` Extracts the znode name of a peer cluster from a ZK path
`private boolean`	`refreshOtherRegionServersList()` Reads the list of region servers from ZK and atomically clears our local view of it and replaces it with the updated list.
`private List<String>`	`refreshPeersList(String path)` Verify if this event is meant for us, and if so then get the latest peers' list from ZK.
`void`	`registerListener(ReplicationListener listener)` Register a replication listener to receive replication events.
`void`	`removeListener(ReplicationListener listener)`

Methods inherited from class org.apache.hadoop.hbase.replication.ReplicationStateZKBase
getListOfReplicatorsZK, isPeerPath, peerExists, toByteArray

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - LOG
```
private static final org.apache.commons.logging.Log LOG
```
  - stopper
```
private final Stoppable stopper
```
  - listeners
```
private final List<ReplicationListener> listeners
```
  - otherRegionServers
```
private final ArrayList<String> otherRegionServers
```
  - replicationPeers
```
private final ReplicationPeers replicationPeers
```
- Constructor Detail
  - ReplicationTrackerZKImpl
```
public ReplicationTrackerZKImpl(ZooKeeperWatcher zookeeper,
                        ReplicationPeers replicationPeers,
                        org.apache.hadoop.conf.Configuration conf,
                        Abortable abortable,
                        Stoppable stopper)
```
- Method Detail
  - registerListener
```
public void registerListener(ReplicationListener listener)
```
    Description copied from interface: ReplicationTracker
    
    Register a replication listener to receive replication events.
    
    Specified by:
    
    registerListener in interface ReplicationTracker
  - removeListener
```
public void removeListener(ReplicationListener listener)
```
    Specified by:
    
    removeListener in interface ReplicationTracker
  - getListOfRegionServers
```
public List<String> getListOfRegionServers()
```
    Return a snapshot of the current region servers.
    
    Specified by:
    
    getListOfRegionServers in interface ReplicationTracker
    
    Returns:
    List of region servers.
  - refreshPeersList
```
private List<String> refreshPeersList(String path)
```
    Verify if this event is meant for us, and if so then get the latest peers' list from ZK. Also reset the watches.
    
    Parameters:
    path - path to check against
    
    Returns:
    A list of peers' identifiers if the event concerns this watcher, else null.
  - getPeersZNode
```
private String getPeersZNode()
```
  - getZNodeName
```
private String getZNodeName(String fullPath)
```
    Extracts the znode name of a peer cluster from a ZK path
    
    Parameters:
    fullPath - Path to extract the id from
    
    Returns:
    the id or an empty string if path is invalid
  - refreshOtherRegionServersList
```
private boolean refreshOtherRegionServersList()
```
    Reads the list of region servers from ZK and atomically clears our local view of it and replaces it with the updated list.
    
    Returns:
    true if the local list of the other region servers was updated with the ZK data (even if it was empty), false if the data was missing in ZK
  - getRegisteredRegionServers
```
private List<String> getRegisteredRegionServers()
```
    Get a list of all the other region servers in this cluster and set a watch
    
    Returns:
    a list of server nanes

Class ReplicationTrackerZKImpl

Nested Class Summary

Field Summary

Fields inherited from class org.apache.hadoop.hbase.replication.ReplicationStateZKBase

Constructor Summary

Method Summary

Methods inherited from class org.apache.hadoop.hbase.replication.ReplicationStateZKBase

Methods inherited from class java.lang.Object

Field Detail

LOG

stopper

listeners

otherRegionServers

replicationPeers

Constructor Detail

ReplicationTrackerZKImpl

Method Detail

registerListener

removeListener

getListOfRegionServers

refreshPeersList

getPeersZNode

getZNodeName

refreshOtherRegionServersList

getRegisteredRegionServers