ZKClusterId (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.zookeeper.ZKClusterId

```
@InterfaceAudience.Private
public class ZKClusterId
extends Object
```
Publishes and synchronizes a unique identifier specific to a given HBase cluster. The stored identifier is read from the file system by the active master on startup, and is subsequently available to all watchers (including clients).

Field Summary

Fields
Modifier and Type Field and Description

private Abortable abortable

private String id

private ZooKeeperWatcher watcher

Fields
Modifier and Type	Field and Description
`private Abortable`	`abortable`
`private String`	`id`
`private ZooKeeperWatcher`	`watcher`

Constructor Summary

Constructors
Constructor and Description

ZKClusterId(ZooKeeperWatcher watcher, Abortable abortable)

Constructors
Constructor and Description
`ZKClusterId(ZooKeeperWatcher watcher, Abortable abortable)`

Method Summary

Methods
Modifier and Type	Method and Description
`String`	`getId()`
`static UUID`	`getUUIDForCluster(ZooKeeperWatcher zkw)` Get the UUID for the provided ZK watcher.
`boolean`	`hasId()`
`static String`	`readClusterIdZNode(ZooKeeperWatcher watcher)`
`static void`	`setClusterId(ZooKeeperWatcher watcher, ClusterId id)`

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

Field Detail

watcher
```
private ZooKeeperWatcher watcher
```

abortable
```
private Abortable abortable
```

id
```
private String id
```

Constructor Detail

ZKClusterId

public ZKClusterId(ZooKeeperWatcher watcher,
           Abortable abortable)

Method Detail

hasId
```
public boolean hasId()
```

getId
```
public String getId()
```

readClusterIdZNode

public static String readClusterIdZNode(ZooKeeperWatcher watcher)
                                 throws org.apache.zookeeper.KeeperException

Throws:: org.apache.zookeeper.KeeperException

setClusterId

public static void setClusterId(ZooKeeperWatcher watcher,
                ClusterId id)
                         throws org.apache.zookeeper.KeeperException

Throws:: org.apache.zookeeper.KeeperException

getUUIDForCluster
```
public static UUID getUUIDForCluster(ZooKeeperWatcher zkw)
                              throws org.apache.zookeeper.KeeperException
```
Get the UUID for the provided ZK watcher. Doesn't handle any ZK exceptions

Parameters:
zkw - watcher connected to an ensemble

Returns:
the UUID read from zookeeper

Throws:

org.apache.zookeeper.KeeperException

Class ZKClusterId

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

watcher

abortable

id

Constructor Detail

ZKClusterId

Method Detail

hasId

getId

readClusterIdZNode

setClusterId

getUUIDForCluster