org.gcube.common.core.utils.handlers
Class GCUBEStagingServiceHandler<CLIENT extends GCUBEServiceClient>

java.lang.Object
  org.gcube.common.core.utils.handlers.GCUBEHandler<CLIENT>
      org.gcube.common.core.utils.handlers.GCUBEServiceHandler<CLIENT>
          org.gcube.common.core.utils.handlers.GCUBEStatefulServiceHandler<CLIENT>
              org.gcube.common.core.utils.handlers.GCUBEStagingServiceHandler<CLIENT>

Type Parameters:

CLIENT - the type of the handled object. It must implement the GCUBEServiceClient interface.

All Implemented Interfaces:

GCUBEIHandler<CLIENT>, Lifetime<CLIENT>

Direct Known Subclasses:

StagingCall.StagingHandler

public abstract class GCUBEStagingServiceHandler<CLIENT extends GCUBEServiceClient>
extends GCUBEStatefulServiceHandler<CLIENT>

Abstract extension of GCUBEStatefulServiceHandler which extends its best-attempt strategy to the case in which instances of the target port-type can be created through factory port-types. The strategy extends GCUBEStatefulServiceHandler's by:

(1) Discovering factories whenever no instance can be found of the target port-type;
(2) Interacting with each factory to create an instance of the target port-type, until one instance has been created;
(3) Interacting with the created instance of the target port-type.

To completely define strategy, subclasses must implement the abstract methods required by GCUBEStatefulServiceHandler as well as the following abstract methods:

(a) findFactories() to discover factories;
(b) createInstance(EndpointReferenceType) to interact with a factory to create an instance of the target port-type;

Author:

Fabio Simeoni (University of Strathclyde)

Nested Class Summary

Nested classes/interfaces inherited from class org.gcube.common.core.utils.handlers.GCUBEServiceHandler

GCUBEServiceHandler.NoQueryResultException

Field Summary

Fields inherited from class org.gcube.common.core.utils.handlers.GCUBEHandler

handled, logger, producer

Constructor Summary

GCUBEStagingServiceHandler()
Creates an instance.

GCUBEStagingServiceHandler(CLIENT client)
Creates an instance to act on or on behalf of a service client.

Method Summary

protected org.apache.axis.message.addressing.EndpointReferenceType	_createInstance(org.apache.axis.message.addressing.EndpointReferenceType epr) Used internally to wrap createInstance(EndpointReferenceType) and handle its failures. If createInstance(EndpointReferenceType) fails with a GCUBEFault, it propagates the GCUBEException which models the fault most specifically.
protected abstract org.apache.axis.message.addressing.EndpointReferenceType	createInstance(org.apache.axis.message.addressing.EndpointReferenceType epr) Interacts with a factory to create an instance of the target port-type.
protected abstract List<org.apache.axis.message.addressing.EndpointReferenceType>	findFactories() Returns a list of EPRs to factories.
protected List<org.apache.axis.message.addressing.EndpointReferenceType>	getFactories() Returns a non-empty list of EPRs to factories.
protected List<org.apache.axis.message.addressing.EndpointReferenceType>	getInstances() Returns a non-empty list of EPRs to instances of the target port-type.
protected org.apache.axis.message.addressing.EndpointReferenceType	tryFactories(List<org.apache.axis.message.addressing.EndpointReferenceType> eprs) Interacts with a list of factories to spawn an instance of the target port-type.

Methods inherited from class org.gcube.common.core.utils.handlers.GCUBEStatefulServiceHandler

findInstances, findWSResources

Methods inherited from class org.gcube.common.core.utils.handlers.GCUBEServiceHandler

_interact, cacheEPR, clearCachedEPR, getAttempts, getCachedEPR, getCacheKey, getTargetPortTypeName, interact, run, setAttempts, tryInstances

Methods inherited from class org.gcube.common.core.utils.handlers.GCUBEHandler

clearBlackboard, getBlackboard, getHandled, getId, getLogger, getName, getScopeManager, getSecurityManager, getState, notify, setBlackboard, setHandled, setLogger, setName, setScopeManager, setSecurityManager, setState, subscribe, undo, unsubscribe

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.gcube.common.core.utils.handlers.lifetime.Lifetime

getState

Methods inherited from interface org.gcube.common.core.utils.handlers.GCUBEIHandler

clearBlackboard, getBlackboard, getHandled, getId, getLogger, getName, getScopeManager, getSecurityManager, setBlackboard, setHandled, setLogger, setName, setScopeManager, setSecurityManager, subscribe, undo, unsubscribe

Constructor Detail

GCUBEStagingServiceHandler

public GCUBEStagingServiceHandler()

Creates an instance.

GCUBEStagingServiceHandler

public GCUBEStagingServiceHandler(CLIENT client)

Creates an instance to act on or on behalf of a service client.

Parameters:

client - the client.

Method Detail

getInstances

protected List<org.apache.axis.message.addressing.EndpointReferenceType> getInstances()
                                                                               throws Exception

Returns a non-empty list of EPRs to instances of the target port-type. The list contains either all the instances returned by getInstances() or, if none is returned, the single instance spawned as the result of the first successful interaction with a factory returned by getFactories().

Overrides:

getInstances in class GCUBEServiceHandler<CLIENT extends GCUBEServiceClient>

Returns:

the list of EPRs.

Throws:

Exception - if no EPRs can be returned.

tryFactories

protected org.apache.axis.message.addressing.EndpointReferenceType tryFactories(List<org.apache.axis.message.addressing.EndpointReferenceType> eprs)
                                                                         throws Exception

Interacts with a list of factories to spawn an instance of the target port-type.

Parameters:

eprs - the EPRs of the factories.

Returns:

the EPR of the spawned instance.

Throws:

Exception - if no interaction is successful.

getFactories

protected List<org.apache.axis.message.addressing.EndpointReferenceType> getFactories()
                                                                               throws Exception,
                                                                                      GCUBEServiceHandler.NoQueryResultException

Returns a non-empty list of EPRs to factories.

Returns:

the list of EPRs.

Throws:

NoQueryResultException - if no factory can be found.

Exception - if no EPR can be returned.

GCUBEServiceHandler.NoQueryResultException

_createInstance

protected org.apache.axis.message.addressing.EndpointReferenceType _createInstance(org.apache.axis.message.addressing.EndpointReferenceType epr)
                                                                            throws Exception

Used internally to wrap createInstance(EndpointReferenceType) and handle its failures.
If createInstance(EndpointReferenceType) fails with a GCUBEFault, it propagates the GCUBEException which models the fault most specifically.

Parameters:

epr - the EPR of a factory.

Throws:

Exception - if no instance could be created.

See Also:

createInstance(EndpointReferenceType)

findFactories

protected abstract List<org.apache.axis.message.addressing.EndpointReferenceType> findFactories()
                                                                                         throws Exception

Returns a list of EPRs to factories.

Returns:

the list of EPRs.

Throws:

Exception - if no EPR can be returned.

createInstance

protected abstract org.apache.axis.message.addressing.EndpointReferenceType createInstance(org.apache.axis.message.addressing.EndpointReferenceType epr)
                                                                                    throws Exception

Interacts with a factory to create an instance of the target port-type.

Parameters:

epr - the EPR of the factory.

Returns:

the EPR of the instance.

Throws:

Exception - if the interaction does not complete successfully.