Package org.apache.hadoop.hbase.client

Class ClusterStatusListener

java.lang.Object

org.apache.hadoop.hbase.client.ClusterStatusListener

All Implemented Interfaces:

Closeable, AutoCloseable

@Private
class ClusterStatusListener
extends Object
implements Closeable

A class that receives the cluster status, and provide it as a set of service to the client. Today, manages only the dead server list. The class is abstract to allow multiple implementations, from ZooKeeper to multicast based.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ClusterStatusListener.DeadServerHandler	Class to be extended to manage a new dead server.
(package private) static interface	ClusterStatusListener.Listener	The interface to be implemented by a listener of a cluster status event.
(package private) class	ClusterStatusListener.MulticastListener	An implementation using a multicast message between the master & the client.

Field Summary

Fields

Modifier and Type	Field	Description
protected final ClusterStatusListener.DeadServerHandler	deadServerHandler
private final List<ServerName>	deadServers
static final Class<? extends ClusterStatusListener.Listener>	DEFAULT_STATUS_LISTENER_CLASS
private final ClusterStatusListener.Listener	listener
private static final org.slf4j.Logger	LOG
static final String	STATUS_LISTENER_CLASS	The implementation class to use to read the status.

Constructor Summary

Constructors

Constructor	Description
ClusterStatusListener(ClusterStatusListener.DeadServerHandler dsh, org.apache.hadoop.conf.Configuration conf, Class<? extends ClusterStatusListener.Listener> listenerClass)

Method Summary

Modifier and Type	Method	Description
void	close()
boolean	isDeadServer(ServerName sn)	Check if we know if a server is dead.
void	receive(ClusterMetrics ncs)	Acts upon the reception of a new cluster status.

Methods inherited from class java.lang.Object

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

Field Details

LOG

private static final org.slf4j.Logger LOG

deadServers

private final List<ServerName> deadServers

deadServerHandler

protected final ClusterStatusListener.DeadServerHandler deadServerHandler

listener

private final ClusterStatusListener.Listener listener

STATUS_LISTENER_CLASS

public static final String STATUS_LISTENER_CLASS

The implementation class to use to read the status.

See Also:

• Constant Field Values

DEFAULT_STATUS_LISTENER_CLASS

public static final Class<? extends ClusterStatusListener.Listener> DEFAULT_STATUS_LISTENER_CLASS

Constructor Details

ClusterStatusListener

public ClusterStatusListener(ClusterStatusListener.DeadServerHandler dsh,
 org.apache.hadoop.conf.Configuration conf,
 Class<? extends ClusterStatusListener.Listener> listenerClass)
                      throws IOException

Throws:

IOException

Method Details

receive

public void receive(ClusterMetrics ncs)

Acts upon the reception of a new cluster status.

Parameters:

ncs - the cluster status

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

isDeadServer

public boolean isDeadServer(ServerName sn)

Check if we know if a server is dead.

Parameters:

sn - the server name to check.

Returns:

true if we know for sure that the server is dead, false otherwise.