Rio Project 4.2 API Documentation

org.rioproject.fdh
Class AdminFaultDetectionHandler

java.lang.Object
  org.rioproject.fdh.AbstractFaultDetectionHandler
      org.rioproject.fdh.AdminFaultDetectionHandler

All Implemented Interfaces:

FaultDetectionHandler<ServiceID>

public class AdminFaultDetectionHandler
extends AbstractFaultDetectionHandler

The AdminFaultDetectionHandler is used to monitor services that implement the Administrable interface.

If the service implements the Administrable interface, the AdminFaultDetectionHandler invokes the Administrable.getAdmin() method periodically. If the method invocation returns successfully, the service is assumed to be available. If the method invocation results in a failure, and all retry attempts have failed, the AdminFaultDetectionHandler will notify FaultDetectionListener instances of the failure.

Additionally, the AdminFaultDetectionHandler will register with Lookup Services for ServiceRegistrar.TRANSITION_MATCH_NOMATCH transitions for the service being monitored. If the service is adminstratively removed from the network, the transition will be noted and FaultDetectionListener instances will be notified of the failure.

If the service does not implement the net.jini.admin.Administrable interface, the AdminFaultDetectionHandler will only create the event consumer for Lookup Service TRANSITION_MATCH_NOMATCH transitions.

Configuring AdminFaultDetectionHandler

This implementation of AdminFaultDetectionHandler supports the following configuration entries; where each configuration entry name is associated with the component name org.rioproject.fdh.AdminFaultDetectionHandler.

• invocationDelay

  Type:	long
  Default:	60*1000 (60 seconds)
  Description:	The amount of time in milliseconds to wait between Administrable.getAdmin() method invocations

• retryCount

  Type:	int
  Default:	3
  Description:	The number of times to retry connecting to the service when invoking the Administrable.getAdmin() method. If the service cannot be reached within the retry count specified the service will be determined to be unreachable

• retryTimeout

  Type:	long
  Default:	1000 (1 second)
  Description:	How long to wait between retries (in milliseconds). This value will be used between retry attempts, waiting the specified amount of time to retry

The amount of time it takes for the AdminFaultDetectionHandler to determine service failure for a service that implements the Administrable interface is calculated as follows :

 ((num_retries + 1) * (connectivity_timeout)) + (retry_delay * num_retries)
 

Author:

Dennis Reedy

Nested Class Summary

Nested classes/interfaces inherited from class org.rioproject.fdh.AbstractFaultDetectionHandler

AbstractFaultDetectionHandler.ServiceMonitor

Field Summary

static String

INVOCATION_DELAY_KEY

Fields inherited from class org.rioproject.fdh.AbstractFaultDetectionHandler

config, configArgs, DEFAULT_RETRY_COUNT, DEFAULT_RETRY_TIMEOUT, proxy, RETRY_COUNT_KEY, RETRY_TIMEOUT_KEY, retryCount, retryTimeout, serviceMonitor, terminating

Constructor Summary

AdminFaultDetectionHandler()

Method Summary

protected AbstractFaultDetectionHandler.ServiceMonitor	getServiceMonitor() Get the class which implements the ServiceMonitor
void	setConfiguration(String[] configArgs) Set configuration attributes for the FaultDetectionHandler.
void	setInvocationDelay(long invocationDelay)

Methods inherited from class org.rioproject.fdh.AbstractFaultDetectionHandler

getName, monitor, notifyListeners, register, setRetryCount, setRetryTimeout, terminate, unregister

Methods inherited from class java.lang.Object

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

Field Detail

INVOCATION_DELAY_KEY

public static final String INVOCATION_DELAY_KEY

See Also:

Constant Field Values

Constructor Detail

AdminFaultDetectionHandler

public AdminFaultDetectionHandler()

Method Detail

setConfiguration

public void setConfiguration(String[] configArgs)

Description copied from interface: FaultDetectionHandler

Set configuration attributes for the FaultDetectionHandler.

Parameters:

configArgs - Configuration attributes a FaultDetectionHandler will use to monitor the service. Values are specific to a concrete instance of the FaultDetectionHandler

See Also:

FaultDetectionHandler.setConfiguration(java.lang.String[])

setInvocationDelay

public void setInvocationDelay(long invocationDelay)

getServiceMonitor

protected AbstractFaultDetectionHandler.ServiceMonitor getServiceMonitor()
                                                                  throws Exception

Get the class which implements the ServiceMonitor

Specified by:

getServiceMonitor in class AbstractFaultDetectionHandler

Returns:

A ServiceMonitor

Throws:

Exception - if the ServiceMonitor cannot be created