org.apache.hadoop.hbase.zookeeper
Class RootRegionTracker

java.lang.Object
  org.apache.hadoop.hbase.zookeeper.ZooKeeperListener
      org.apache.hadoop.hbase.zookeeper.ZooKeeperNodeTracker
          org.apache.hadoop.hbase.zookeeper.RootRegionTracker

public class RootRegionTracker
extends ZooKeeperNodeTracker

Tracks the root region server location node in zookeeper. Root region location is set by RootLocationEditor usually called out of RegionServerServices. This class has a watcher on the root location and notices changes.

Field Summary

Fields inherited from class org.apache.hadoop.hbase.zookeeper.ZooKeeperNodeTracker

abortable, node

Fields inherited from class org.apache.hadoop.hbase.zookeeper.ZooKeeperListener

watcher

Constructor Summary

RootRegionTracker(ZooKeeperWatcher watcher, Abortable abortable)
Creates a root region location tracker.

Method Summary

HServerAddress	getRootRegionLocation() Gets the root region location, if available.
boolean	isLocationAvailable() Checks if the root region location is available.
HServerAddress	waitRootRegionLocation(long timeout) Gets the root region location, if available, and waits for up to the specified timeout if not immediately available.

Methods inherited from class org.apache.hadoop.hbase.zookeeper.ZooKeeperNodeTracker

blockUntilAvailable, blockUntilAvailable, getData, getNode, nodeCreated, nodeDataChanged, nodeDeleted, start, stop

Methods inherited from class org.apache.hadoop.hbase.zookeeper.ZooKeeperListener

nodeChildrenChanged

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RootRegionTracker

public RootRegionTracker(ZooKeeperWatcher watcher,
                         Abortable abortable)

Creates a root region location tracker.

After construction, use ZooKeeperNodeTracker.start() to kick off tracking.

Parameters:

watcher -

abortable -

Method Detail

isLocationAvailable

public boolean isLocationAvailable()

Checks if the root region location is available.

Returns:

true if root region location is available, false if not

getRootRegionLocation

public HServerAddress getRootRegionLocation()
                                     throws java.lang.InterruptedException

Gets the root region location, if available. Null if not. Does not block.

Returns:

server address for server hosting root region, null if none available

Throws:

java.lang.InterruptedException

waitRootRegionLocation

public HServerAddress waitRootRegionLocation(long timeout)
                                      throws java.lang.InterruptedException

Gets the root region location, if available, and waits for up to the specified timeout if not immediately available.

Parameters:

timeout - maximum time to wait, in millis

Returns:

server address for server hosting root region, null if timed out

Throws:

java.lang.InterruptedException - if interrupted while waiting