com.j_spaces.core.cluster.startup

Class GigaSpacesFaultDetectionHandler

java.lang.Object

com.j_spaces.core.cluster.startup.AbstractFaultDetectionHandler

com.j_spaces.core.cluster.startup.GigaSpacesFaultDetectionHandler

All Implemented Interfaces:

FaultDetectionHandler

public class GigaSpacesFaultDetectionHandler
extends AbstractFaultDetectionHandler

Provides support to determine the reachability of the GigaSpace service. The GigaSpacesFaultDetectionHandler can be used to monitor services which implement the com.j_spaces.core.IJSpace interface (as well as for services that do not implement this interface).

If the service does implement the com.j_spaces.core.IJSpace, interface, the GigaSpacesFaultDetectionHandler will ensure that the proxy being used is a non-clustered proxy, then invoke the IJSpace.ping() method periodically. If this method invocation returns succesfully, the service is assumed to be available. If this method invocation results in a failure, and all retry attempts have failed, the GigaSpacesFaultDetectionHandler will notify FaultDetectionListener instances of the failure.

Additionally, the GigaSpacesFaultDetectionHandler 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 com.j_spaces.core.IJSpace interface, the GigaSpacesFaultDetectionHandler will periodically invoke the IJSpace.ping() method, but will only create the event consumer for Lookup Service TRANSITION_MATCH_NOMATCH transitions.

Configuring GigaSpacesFaultDetectionHandler

This implementation of GigaSpacesFaultDetectionHandler supports the following configuration entries; where each configuration entry name is associated with the component name com.gigaspaces.grid.handler.GigaSpacesFaultDetectionHandler.

• invocationDelay

  Type:	long
  Default:	30*1000 (30 seconds)
  Description:	The amount of time in milliseconds to wait between IJSpace.ping() method invocations

• retryCount

  Type:	int
  Default:	3
  Description:	The number of times to retry connecting to the service when invoking the IJSpace.ping() 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 GigaSpacesFaultDetectionHandler to determine service failure for a service which implements the IJSpace interface is calculated as follows :

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

Nested Class Summary

Nested classes/interfaces inherited from class com.j_spaces.core.cluster.startup.AbstractFaultDetectionHandler

AbstractFaultDetectionHandler.ServiceMonitor

Field Summary

Fields

Modifier and Type	Field and Description
static String	INVOCATION_DELAY_KEY

Fields inherited from class com.j_spaces.core.cluster.startup.AbstractFaultDetectionHandler

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

Constructor Summary

Constructors

Constructor and Description
GigaSpacesFaultDetectionHandler()

Method Summary

Modifier and Type	Method and Description
Object	getSpaceProxy()
protected void	monitor() Get the class which implements the ServiceMonitor
void	monitor(Object proxy, ServiceID serviceID) Override the monitor method to ensure a non-clustered proxy is used
void	setConfiguration(String[] configArgs) Set configuration attributes for the FaultDetectionHandler.

Methods inherited from class com.j_spaces.core.cluster.startup.AbstractFaultDetectionHandler

getName, notifyListeners, register, terminate

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

GigaSpacesFaultDetectionHandler

public GigaSpacesFaultDetectionHandler()

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[])

monitor

public void monitor(Object proxy,
                    ServiceID serviceID)
             throws Exception

Override the monitor method to ensure a non-clustered proxy is used

Specified by:

monitor in interface FaultDetectionHandler

Overrides:

monitor in class AbstractFaultDetectionHandler

Parameters:

proxy - The service that the FaultDetectionHandler will monitor, must not be null

serviceID - An Object representing a unique service identifier for the service being monitored, must not be null

Throws:

Exception - If there are abnormal conditions encountered

NullPointerException - if required parameters are null

See Also:

FaultDetectionHandler.monitor(java.lang.Object, java.lang.Object, net.jini.lookup.LookupCache)

monitor

protected void monitor()
                throws Exception

Get the class which implements the ServiceMonitor

Specified by:

monitor in class AbstractFaultDetectionHandler

Throws:

Exception

getSpaceProxy

public Object getSpaceProxy()