org.softamis.cluster4spring.support.provider
Class AbstractUrlListEndpointProvider<E extends Endpoint<SI>,SI extends ServiceMoniker>

java.lang.Object
  org.softamis.cluster4spring.support.provider.BaseEndpointProvider<E,SI>
      org.softamis.cluster4spring.support.provider.MultiURLEndpointProvider<E,SI>
          org.softamis.cluster4spring.support.provider.AbstractUrlListEndpointProvider<E,SI>

Type Parameters:

SI - type of data used to invoke remote service (such as remote service URL)

E - type of endpoints that could be created by this factory

All Implemented Interfaces:

EndpointProvider<E,SI>, org.springframework.beans.factory.InitializingBean

Direct Known Subclasses:

AbstractDiscoveringEndpointProvider, UrlListEndpointProvider

public abstract class AbstractUrlListEndpointProvider<E extends Endpoint<SI>,SI extends ServiceMoniker>
extends MultiURLEndpointProvider<E,SI>

Base abstract class to implement endpoint providers which provide endpoints based on list of endpoints available for service and which maintains internal cache of discovered endpoints.

Author:

Andrew Sazonov

Field Summary

protected java.lang.Object	fCacheLock Object used as lock to access cache of endpoints
protected java.util.List<E>	fEndpointsCache List which contains discovered endpoints
protected static org.apache.commons.logging.Log	fLog

Fields inherited from class org.softamis.cluster4spring.support.provider.MultiURLEndpointProvider

fEndpointSelectionPolicy

Fields inherited from class org.softamis.cluster4spring.support.provider.BaseEndpointProvider

fCacheEndpoints

Constructor Summary

protected

AbstractUrlListEndpointProvider()

Method Summary

void	afterPropertiesSet() Invoked by Spring as part of bean lifecycle.
protected java.util.List<E>	doGetCachedEndpoints() Utility method to obtain list of enpoints from cache.
protected abstract java.util.List<E>	doRefreshServiceEndpointsList(org.springframework.remoting.support.RemoteInvocationFactory aRemoteInvocationFactory, EndpointFactory<E,SI> aEndpointFactory, java.lang.String aBeanName) Creates list of endpoints available for service.
protected java.util.List<E>	getCachedEndpoints(org.springframework.remoting.support.RemoteInvocationFactory aRemoteInvocationFactory, EndpointFactory<E,SI> aEndpointFactory, java.lang.String aBeanName) Obtains endpoints from endpoints cache.
protected java.util.List<E>	getServiceEndpointsList(org.springframework.remoting.support.RemoteInvocationFactory aRemoteInvocationFactory, EndpointFactory<E,SI> aEndpointFactory, java.lang.String aBeanName) Performs actual obtaining of list of available endpoints.
void	refresh(org.springframework.remoting.support.RemoteInvocationFactory aRemoteInvocationFactory, EndpointFactory<E,SI> aEndpointFactory, java.lang.String aBeanName) Refreshes internal state of provider.
protected void	saveFreshEndpointsToCache(java.util.List<E> aEndpoints) Save obtained endpoints to endpoints cache.

Methods inherited from class org.softamis.cluster4spring.support.provider.MultiURLEndpointProvider

createDefaultEndpointSelectionPolicy, getEndpoint, setEndpointSelectionPolicy

Methods inherited from class org.softamis.cluster4spring.support.provider.BaseEndpointProvider

doCreateServiceEndpoint, isCacheEndpoints, setCacheEndpoints

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.softamis.cluster4spring.support.EndpointProvider

markInvalid

Field Detail

fLog

protected static final org.apache.commons.logging.Log fLog

fEndpointsCache

protected java.util.List<E extends Endpoint<SI>> fEndpointsCache

List which contains discovered endpoints

fCacheLock

protected final java.lang.Object fCacheLock

Object used as lock to access cache of endpoints

Constructor Detail

AbstractUrlListEndpointProvider

protected AbstractUrlListEndpointProvider()

Method Detail

afterPropertiesSet

public void afterPropertiesSet()
                        throws java.lang.Exception

Description copied from class: MultiURLEndpointProvider

Invoked by Spring as part of bean lifecycle. Used to check whether endpoints selection policy is specified during bean configuration. If one is not specified, default endpoints selection policy is created.

Specified by:

afterPropertiesSet in interface org.springframework.beans.factory.InitializingBean

Overrides:

afterPropertiesSet in class MultiURLEndpointProvider<E extends Endpoint<SI>,SI extends ServiceMoniker>

Throws:

java.lang.Exception

See Also:

MultiURLEndpointProvider.createDefaultEndpointSelectionPolicy()

refresh

public void refresh(org.springframework.remoting.support.RemoteInvocationFactory aRemoteInvocationFactory,
                    EndpointFactory<E,SI> aEndpointFactory,
                    java.lang.String aBeanName)
             throws org.springframework.remoting.RemoteAccessException

Refreshes internal state of provider. If configured to cache endpoints, tries to obtain list of endpoints available and saves it to cache. Otherwise, silently does nothing since endpoint list will be obtained by request.

Parameters:

aRemoteInvocationFactory - factory used to create remote invocation

aEndpointFactory - factory used to create endpoints

aBeanName - name of bean that is used as proxy for remote service

Throws:

org.springframework.remoting.RemoteAccessException - throw if exception occured during refreshing

getServiceEndpointsList

protected java.util.List<E> getServiceEndpointsList(org.springframework.remoting.support.RemoteInvocationFactory aRemoteInvocationFactory,
                                                    EndpointFactory<E,SI> aEndpointFactory,
                                                    java.lang.String aBeanName)
                                                                  throws org.springframework.remoting.RemoteAccessException

Performs actual obtaining of list of available endpoints. If configured to cache endpoints, tries to provide endpoints from the endpoints cache. Otherwise, tries to create available endpoints.

Specified by:

getServiceEndpointsList in class MultiURLEndpointProvider<E extends Endpoint<SI>,SI extends ServiceMoniker>

Parameters:

aRemoteInvocationFactory - factory used for remote invocation

aEndpointFactory - factory used for endpoints creation

aBeanName -

Returns:

list of endpoints available for service

Throws:

org.springframework.remoting.RemoteAccessException

See Also:

BaseEndpointProvider.setCacheEndpoints(boolean)

getCachedEndpoints

protected java.util.List<E> getCachedEndpoints(org.springframework.remoting.support.RemoteInvocationFactory aRemoteInvocationFactory,
                                               EndpointFactory<E,SI> aEndpointFactory,
                                               java.lang.String aBeanName)

Obtains endpoints from endpoints cache. If endpoints cache is null (i.e there were no endpoints stored there), tries to perform refresh.

Parameters:

aRemoteInvocationFactory - factory to create remote invocations

aEndpointFactory - factory used to create endpoints

aBeanName -

Returns:

list of endpoints

doGetCachedEndpoints

protected java.util.List<E> doGetCachedEndpoints()

Utility method to obtain list of enpoints from cache. Includes synchronization related code.

Returns:

list of cached endpoints

saveFreshEndpointsToCache

protected void saveFreshEndpointsToCache(java.util.List<E> aEndpoints)

Save obtained endpoints to endpoints cache.

Parameters:

aEndpoints - list of endpoints to store in cache

doRefreshServiceEndpointsList

protected abstract java.util.List<E> doRefreshServiceEndpointsList(org.springframework.remoting.support.RemoteInvocationFactory aRemoteInvocationFactory,
                                                                   EndpointFactory<E,SI> aEndpointFactory,
                                                                   java.lang.String aBeanName)
                                                                                 throws org.springframework.remoting.RemoteAccessException

Creates list of endpoints available for service. Inherited classes will override it to provide specific implementation.

Parameters:

aRemoteInvocationFactory - factory used to create remote invocation

aEndpointFactory - factory used to create endpoints

aBeanName -

Returns:

list of created endpoints

Throws:

org.springframework.remoting.RemoteAccessException - throws if list of endpoints could not be created