org.lsst.ccs.gconsole.plugins.monitor

Interface DisplayChannel

All Known Implementing Classes:

DisplayChannelMulti, DisplayChannelSingle

public interface DisplayChannel

Represents a channel displayed by a monitoring views. Each DisplayChannel is identified by a display path unique within a monitoring view, and is linked to one or more original data channels that contribute to it. Optionally, DisplayChannel can be assigned an Updatable target that will be automatically updated whenever there are changes in the channel data.

Equality of display channels should be implemented to be based on their paths.

Author:

onoprien

Method Summary

Modifier and Type	Method and Description
default void	addChannel(AgentChannel channel) Adds an original published data channel to the list of channels associated with this display channel.
default void	appendChannel(AgentChannel channel) Appends an original published data channel to the list of channels associated with this display channel.
default AgentChannel	getChannel() Returns the original published data channel associated with this display channel.
default List<AgentChannel>	getChannels() Returns an unmodifiable list of original published data channels associated with this display channel.
String	getPath() Returns the display path associated with this channel.
Updatable	getTarget() Returns the object that should be notified whenever there are changes to data channels associated with this display channel.
default boolean	purgeOfflineChannels(List<String> agentNames) Removes all offline channels from the specified agents.
default boolean	removeChannel(String path) Removes an original published data channel from the list of channels associated with this display channel.
void	setChannel(AgentChannel channel) Sets the original published data channel associated with this display channel.
default void	setChannels(Collection<AgentChannel> channels) Sets the list of original published data channels associated with this display channel.
void	setTarget(Updatable target) Set the object that should be notified whenever there are changes to data channels associated with this display channel.
default void	update(List<String> attributes) Updates the target.

Method Detail

getPath

String getPath()

Returns the display path associated with this channel.

Returns:

Display path.

getTarget

Updatable getTarget()

Returns the object that should be notified whenever there are changes to data channels associated with this display channel.

Returns:

Target to be notified of changes.

setTarget

void setTarget(Updatable target)

Set the object that should be notified whenever there are changes to data channels associated with this display channel.

Parameters:

target - Target to be notified of changes.

getChannel

default AgentChannel getChannel()

Returns the original published data channel associated with this display channel. It is up to implementations to decide what to return if multiple original channels are mapped to this display channel.

Returns:

Data channel, or null if no data channels are associated with this display channel.

getChannels

default List<AgentChannel> getChannels()

Returns an unmodifiable list of original published data channels associated with this display channel.

Returns:

Data channel.

setChannel

void setChannel(AgentChannel channel)

Sets the original published data channel associated with this display channel.

Parameters:

channel - Data channel.

setChannels

default void setChannels(Collection<AgentChannel> channels)

Sets the list of original published data channels associated with this display channel. Any previously associated channels are removed.

Parameters:

channels - Data channels to be associated with this display channel.

Throws:

UnsupportedOperationException - If the provided list contains multiple channels but the implementation only supports single channel association.

addChannel

default void addChannel(AgentChannel channel)

Adds an original published data channel to the list of channels associated with this display channel. If a channel with the same path already exists, it is replaced.

Parameters:

channel - Data channel.

Throws:

UnsupportedOperationException - If the implementation only supports single channel association.

appendChannel

default void appendChannel(AgentChannel channel)

Appends an original published data channel to the list of channels associated with this display channel. Does not check whether the published channel is already present in the list.

Parameters:

channel - Data channel.

Throws:

UnsupportedOperationException - If the implementation only supports single channel association.

removeChannel

default boolean removeChannel(String path)

Removes an original published data channel from the list of channels associated with this display channel.

Parameters:

path - Original path of the channel to be removed.

Returns:

True if this display channel no longer has any data channels associated with it.

Throws:

UnsupportedOperationException - If the implementation only supports single channel association.

purgeOfflineChannels

default boolean purgeOfflineChannels(List<String> agentNames)

Removes all offline channels from the specified agents. The default implementation does nothing and returns false.

Parameters:

agentNames - Agent names.

Returns:

True if this display channel no longer has any data channels associated with it.

update

default void update(List<String> attributes)

Updates the target. The default implementation converts the list of attributes into the list of monitored fields using the target's getAffectedFields(...) method, then calls the appropriate update(...) method of the target. Most classes implementing this interface will not override this method.

Parameters:

attributes - List of attributes whose values might have changed, or null if all attribute values might have changed.