com.redhat.thermostat.backend

Class HostPollingBackend

java.lang.Object

com.redhat.thermostat.backend.BaseBackend

com.redhat.thermostat.backend.HostPollingBackend

All Implemented Interfaces:

Backend, Ordered

public abstract class HostPollingBackend
extends BaseBackend

Convenience Backend class for implementations that will take some action at the Host or system level on a regular interval. Simply extend this class, implement any missing methods, and register one or more HostPollingAction implementations during instantiation.

Field Summary

Fields inherited from interface com.redhat.thermostat.common.Ordered

ORDER_CODE_GROUP, ORDER_CPU_GROUP, ORDER_DEFAULT_GROUP, ORDER_FIRST, ORDER_IO_GROUP, ORDER_LAST, ORDER_MEMORY_GROUP, ORDER_NETWORK_GROUP, ORDER_THREAD_GROUP, ORDER_USER_GROUP

Constructor Summary

Constructors

Constructor and Description
HostPollingBackend(String name, String description, String vendor, Version version, ScheduledExecutorService executor)

Method Summary

Modifier and Type	Method and Description
boolean	activate() Activate the Backend.
boolean	deactivate() Deactivate the Backend.
boolean	isActive()
protected void	registerAction(HostPollingAction action) Register an action to be performed at each polling interval.
void	setObserveNewJvm(boolean newValue) Set whether this backend will attach to new java processes.
protected void	unregisterAction(HostPollingAction action) Unregister an action so that it will no longer be performed at each polling interval.

Methods inherited from class com.redhat.thermostat.backend.BaseBackend

equals, getDescription, getName, getObserveNewJvm, getVendor, getVersion, hashCode, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.redhat.thermostat.common.Ordered

getOrderValue

Constructor Detail

HostPollingBackend

public HostPollingBackend(String name,
                          String description,
                          String vendor,
                          Version version,
                          ScheduledExecutorService executor)

Method Detail

registerAction

protected final void registerAction(HostPollingAction action)

Register an action to be performed at each polling interval. It is recommended that implementations register all such actions during instantiation.

unregisterAction

protected final void unregisterAction(HostPollingAction action)

Unregister an action so that it will no longer be performed at each polling interval. If no such action has been registered, this method has no effect. Depending on thread timing issues, the action may be performed once even after this method has been called.

setObserveNewJvm

public void setObserveNewJvm(boolean newValue)

Description copied from interface: Backend

Set whether this backend will attach to new java processes.

Specified by:

setObserveNewJvm in interface Backend

Overrides:

setObserveNewJvm in class BaseBackend

activate

public final boolean activate()

Description copied from interface: Backend

Activate the Backend. Based on the current configuration, begin pushing data to the Storage layer. If the Backend is already active, this method should have no effect.

This method is called by the framework when the Backend is registered.

Returns:

true if the backend was activated successfully or already active. false if there was an error

deactivate

public final boolean deactivate()

Description copied from interface: Backend

Deactivate the Backend. The backend should release any resources that were obtained as a direct result of a call to Backend.activate(). If the Backend is not active, this method should have no effect

This method is called by the framework when the Backend is deregistered.

Returns:

true if the backend was successfully deactivated or already inactive. false if the backend is still active.

isActive

public final boolean isActive()

Returns:

a boolean indicating whether the backend is currently active on this host