org.apache.synapse.endpoints

Class LoadbalanceEndpoint

java.lang.Object

org.apache.synapse.FaultHandler

org.apache.synapse.endpoints.AbstractEndpoint

org.apache.synapse.endpoints.LoadbalanceEndpoint

All Implemented Interfaces:

Endpoint, ManagedLifecycle, Nameable, PropertyInclude, SynapseArtifact

Direct Known Subclasses:

DynamicLoadbalanceEndpoint, SALoadbalanceEndpoint

public class LoadbalanceEndpoint
extends AbstractEndpoint

A Load balance endpoint contains multiple child endpoints. It routes messages according to the specified load balancing algorithm. This will assume that all immediate child endpoints are identical in state (state is replicated) or state is not maintained at those endpoints. If an endpoint is failing, the failed endpoint is marked as inactive and the message sent to the next endpoint obtained using the load balancing algorithm. If all the endpoints have failed and a parent endpoint is available, onChildEndpointFail(...) method of parent endpoint is called. If a parent is not available, this will call next FaultHandler for the message context.

Field Summary

Fields inherited from class org.apache.synapse.endpoints.AbstractEndpoint

anonymous, artifactContainerName, CHILDREN_JSON_ATT, errorHandler, fileName, initialized, isClusteringEnabled, log, NAME_JSON_ATT, trace, TYPE_JSON_ATT

Constructor Summary

Constructors

Constructor and Description
LoadbalanceEndpoint()

Method Summary

Modifier and Type	Method and Description
protected void	createJsonRepresentation()
void	destroy() This method should implement the destroying of the implemented parts of the configuration.
LoadbalanceAlgorithm	getAlgorithm()
List<org.apache.axis2.clustering.Member>	getMembers()
protected Endpoint	getNextChild(MessageContext synCtx)
void	init(SynapseEnvironment synapseEnvironment) This method should implement the initialization of the implemented parts of the configuration.
boolean	isBuildMessageAtt()
boolean	isFailover()
boolean	isInitialized() NOTE: Override org.apache.synapse.endpoints.AbstractEndpoint#isInitialized() to ensure return true only after LB Endpoint get fully initialized.
void	onChildEndpointFail(Endpoint endpoint, MessageContext synMessageContext) Endpoints that contain other endpoints should implement this method.
boolean	readyToSend() If this endpoint is in inactive state, checks if all immediate child endpoints are still failed.
void	send(MessageContext synCtx) Sends the message context according to an endpoint specific behavior.
void	setAlgorithm(LoadbalanceAlgorithm algorithm)
void	setBuildMessageAtt(boolean build)
void	setBuildMessageAttAvailable(boolean available)
void	setFailover(boolean failover)
void	setMembers(List<org.apache.axis2.clustering.Member> members)
void	startApplicationMembershipTimer()

Methods inherited from class org.apache.synapse.endpoints.AbstractEndpoint

addProperties, addProperty, evaluateProperties, executeEpTypeSpecificFunctions, getArtifactContainerName, getChildren, getCommentsList, getContext, getDefinition, getDescription, getEndpointChildrenAsJson, getErrorHandler, getFileName, getIsEdited, getJsonRepresentation, getMetricsMBean, getName, getParentEndpoint, getProperties, getProperty, getReportingName, handleException, handleException, informFailure, isAnonymous, isLeafEndpoint, isRetry, isSuspendFault, isTimeout, isTraceOn, isTraceOrDebugOn, logOnChildEndpointFail, logSetter, onFault, onSuccess, prepareForEndpointStatistics, removeProperty, setAdvancedProperties, setAnonymous, setArtifactContainerName, setChildren, setCommentsList, setComponentStatisticsId, setContentAware, setDefinition, setDescription, setEnableMBeanStats, setErrorHandler, setErrorOnMessage, setFileName, setForceBuildMC, setIsEdited, setName, setParentEndpoint, toString, traceOrDebug

Methods inherited from class org.apache.synapse.FaultHandler

getStackTrace, handleFault, handleFault

Methods inherited from class java.lang.Object

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

Constructor Detail

LoadbalanceEndpoint

public LoadbalanceEndpoint()

Method Detail

init

public void init(SynapseEnvironment synapseEnvironment)

Description copied from interface: ManagedLifecycle

This method should implement the initialization of the implemented parts of the configuration.

Specified by:

init in interface ManagedLifecycle

Overrides:

init in class AbstractEndpoint

Parameters:

synapseEnvironment - SynapseEnvironment to be used for initialization

destroy

public void destroy()

Description copied from interface: ManagedLifecycle

This method should implement the destroying of the implemented parts of the configuration.

Specified by:

destroy in interface ManagedLifecycle

Overrides:

destroy in class AbstractEndpoint

isInitialized

public boolean isInitialized()

NOTE: Override org.apache.synapse.endpoints.AbstractEndpoint#isInitialized() to ensure return true only after LB Endpoint get fully initialized. This is done to avoid super.isInitialized return true while LoadbalanceEndpoint initializing during request burst *at server startup*

Specified by:

isInitialized in interface Endpoint

Overrides:

isInitialized in class AbstractEndpoint

Returns:

createJsonRepresentation

protected void createJsonRepresentation()

Specified by:

createJsonRepresentation in class AbstractEndpoint

send

public void send(MessageContext synCtx)

Description copied from interface: Endpoint

Sends the message context according to an endpoint specific behavior.

Specified by:

send in interface Endpoint

Overrides:

send in class AbstractEndpoint

Parameters:

synCtx - MessageContext to be sent.

readyToSend

public boolean readyToSend()

If this endpoint is in inactive state, checks if all immediate child endpoints are still failed. If so returns false. If at least one child endpoint is in active state, sets this endpoint's state to active and returns true. As this a sessionless load balancing endpoint having one active child endpoint is enough to consider this as active.

Specified by:

readyToSend in interface Endpoint

Overrides:

readyToSend in class AbstractEndpoint

Returns:

true if active. false otherwise.

onChildEndpointFail

public void onChildEndpointFail(Endpoint endpoint,
                                MessageContext synMessageContext)

Description copied from interface: Endpoint

Endpoints that contain other endpoints should implement this method. It will be called if a child endpoint causes an exception. Action to be taken on such failure is up to the implementation. But it is good practice to first try addressing the issue. If it can't be addressed propagate the exception to parent endpoint by calling parent endpoint's onChildEndpointFail(...) method.

Specified by:

onChildEndpointFail in interface Endpoint

Overrides:

onChildEndpointFail in class AbstractEndpoint

Parameters:

endpoint - The child endpoint which caused the exception.

synMessageContext - MessageContext that was used in the failed attempt.

isFailover

public boolean isFailover()

isBuildMessageAtt

public boolean isBuildMessageAtt()

setFailover

public void setFailover(boolean failover)

getAlgorithm

public LoadbalanceAlgorithm getAlgorithm()

setAlgorithm

public void setAlgorithm(LoadbalanceAlgorithm algorithm)

getNextChild

protected Endpoint getNextChild(MessageContext synCtx)

setMembers

public void setMembers(List<org.apache.axis2.clustering.Member> members)

getMembers

public List<org.apache.axis2.clustering.Member> getMembers()

startApplicationMembershipTimer

public void startApplicationMembershipTimer()

setBuildMessageAtt

public void setBuildMessageAtt(boolean build)

setBuildMessageAttAvailable

public void setBuildMessageAttAvailable(boolean available)