com.aquenos.cassandra.pvarchiver.server.archiving

Class RefreshChannelCommand

java.lang.Object

com.aquenos.cassandra.pvarchiver.server.archiving.ArchiveConfigurationCommand

com.aquenos.cassandra.pvarchiver.server.archiving.RefreshChannelCommand

public final class RefreshChannelCommand
extends ArchiveConfigurationCommand

Command for refreshing a channel. Refreshing a channel results in the channel being shutdown temporarily and being restarted with its configuration reloaded from the database. If a channel has been newly added, it results in the channel being started for the first time. If a channel has been removed, it results in the channel being removed from the active server configuration. If a pending operation has been registered for the channel, the channel is temporarily put into an error state until the pending operation is removed and the channel is refreshed again.

In contrast to most other archive configuration commands, this command is not forwarded to the server that currently owns the channel. Instead, it is always executed by the server specified in the command.

This command object contains all data that is needed for the move operation. Typically, it is passed to the ArchiveConfigurationService, but it might also be sent over the network before actually being processed.

Author:

Sebastian Marsching

Nested Class Summary

Nested classes/interfaces inherited from class com.aquenos.cassandra.pvarchiver.server.archiving.ArchiveConfigurationCommand

ArchiveConfigurationCommand.Type

Constructor Summary

Constructors

Constructor and Description
RefreshChannelCommand(String channelName, UUID serverId) Creates a "refresh channel" command.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
String	getChannelName() Returns the name of the channel that shall be refreshed.
ArchiveConfigurationCommand.Type	getCommandType() Returns the type of the actual command type.
UUID	getServerId() Returns the ID of the server on which the channel shall be refreshed.
int	hashCode()
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

RefreshChannelCommand

public RefreshChannelCommand(String channelName,
                             UUID serverId)

Creates a "refresh channel" command. A refresh operation always succeeds unless there is a communication problem that prevents the command from being actually sent to the target server.

Parameters:

channelName - name of the channel to be refreshed.

serverId - ID of the server on which the channel shall be refreshed. This does not have to be the ID of the server that currently owns the channel. For example, after moving a channel, it should also be refreshed on the old server so that it gets removed from that server's configuration.

Throws:

IllegalArgumentException - if channelName is empty.

NullPointerException - if channelName or serverId is null.

Method Detail

getCommandType

public ArchiveConfigurationCommand.Type getCommandType()

Description copied from class: ArchiveConfigurationCommand

Returns the type of the actual command type. Please refer to the document in the ArchiveConfigurationCommand class or the ArchiveConfigurationCommand.Type enum for a list of types. The return value is never null .

Specified by:

getCommandType in class ArchiveConfigurationCommand

Returns:

type of this command.

getChannelName

public String getChannelName()

Returns the name of the channel that shall be refreshed. The value returned is never null or the empty string.

Returns:

name of the channel to be refreshed.

getServerId

public UUID getServerId()

Returns the ID of the server on which the channel shall be refreshed. The returned is never null.

Returns:

ID of the server on which the channel shall be refreshed.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object