org.apache.camel.processor.loadbalancer
Class FailOverLoadBalancer

java.lang.Object
  org.apache.camel.support.ServiceSupport
      org.apache.camel.processor.loadbalancer.LoadBalancerSupport
          org.apache.camel.processor.loadbalancer.FailOverLoadBalancer

All Implemented Interfaces:

AsyncProcessor, CamelContextAware, Navigate<Processor>, Processor, LoadBalancer, Service, ShutdownableService, StatefulService, SuspendableService, Traceable

public class FailOverLoadBalancer
extends LoadBalancerSupport
implements Traceable, CamelContextAware

This FailOverLoadBalancer will failover to use next processor when an exception occurred

This implementation mirrors the logic from the Pipeline in the async variation as the failover load balancer is a specialized pipeline. So the trick is to keep doing the same as the pipeline to ensure it works the same and the async routing engine is flawless.

Field Summary

Fields inherited from class org.apache.camel.processor.loadbalancer.LoadBalancerSupport

log

Fields inherited from class org.apache.camel.support.ServiceSupport

shutdown, shuttingdown, started, starting, stopped, stopping, suspended, suspending

Constructor Summary

FailOverLoadBalancer()

FailOverLoadBalancer(List<Class<?>> exceptions)

Method Summary

CamelContext	getCamelContext() Get the CamelContext
List<Class<?>>	getExceptions()
int	getMaximumFailoverAttempts()
String	getTraceLabel() Gets the trace label used for logging when tracing is enabled.
boolean	isRoundRobin()
boolean	isRunAllowed() Helper methods so the service knows if it should keep running.
protected Exchange	prepareExchangeForFailover(Exchange exchange) Prepares the exchange for failover
boolean	process(Exchange exchange, AsyncCallback callback) Processes the message exchange.
void	setCamelContext(CamelContext camelContext) Injects the CamelContext
void	setMaximumFailoverAttempts(int maximumFailoverAttempts)
void	setRoundRobin(boolean roundRobin)
protected boolean	shouldFailOver(Exchange exchange) Should the given failed Exchange failover?
String	toString()

Methods inherited from class org.apache.camel.processor.loadbalancer.LoadBalancerSupport

addProcessor, doStart, doStop, getProcessors, hasNext, next, process, removeProcessor

Methods inherited from class org.apache.camel.support.ServiceSupport

doResume, doShutdown, doSuspend, getStatus, getVersion, isStarted, isStarting, isStopped, isStopping, isSuspended, isSuspending, resume, shutdown, start, stop, suspend

Methods inherited from class java.lang.Object

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

Constructor Detail

FailOverLoadBalancer

public FailOverLoadBalancer()

FailOverLoadBalancer

public FailOverLoadBalancer(List<Class<?>> exceptions)

Method Detail

getCamelContext

public CamelContext getCamelContext()

Description copied from interface: CamelContextAware

Get the CamelContext

Specified by:

getCamelContext in interface CamelContextAware

Returns:

camelContext the Camel context

setCamelContext

public void setCamelContext(CamelContext camelContext)

Description copied from interface: CamelContextAware

Injects the CamelContext

Specified by:

setCamelContext in interface CamelContextAware

Parameters:

camelContext - the Camel context

getExceptions

public List<Class<?>> getExceptions()

isRoundRobin

public boolean isRoundRobin()

setRoundRobin

public void setRoundRobin(boolean roundRobin)

getMaximumFailoverAttempts

public int getMaximumFailoverAttempts()

setMaximumFailoverAttempts

public void setMaximumFailoverAttempts(int maximumFailoverAttempts)

shouldFailOver

protected boolean shouldFailOver(Exchange exchange)

Should the given failed Exchange failover?

Parameters:

exchange - the exchange that failed

Returns:

true to failover

isRunAllowed

public boolean isRunAllowed()

Description copied from interface: StatefulService

Helper methods so the service knows if it should keep running. Returns false if the service is being stopped or is stopped.

Specified by:

isRunAllowed in interface StatefulService

Overrides:

isRunAllowed in class ServiceSupport

Returns:

true if the service should continue to run.

process

public boolean process(Exchange exchange,
                       AsyncCallback callback)

Description copied from interface: AsyncProcessor

Processes the message exchange. Similar to Processor.process(org.apache.camel.Exchange), but the caller supports having the exchange asynchronously processed.

If there was a failure processing then the caused Exception would be set on the Exchange.

Specified by:

process in interface AsyncProcessor

Parameters:

exchange - the message exchange

callback - the AsyncCallback will be invoked when the processing of the exchange is completed. If the exchange is completed synchronously, then the callback is also invoked synchronously. The callback should therefore be careful of starting recursive loop.

Returns:

(doneSync) true to continue execute synchronously, false to continue being executed asynchronously

See Also:

AsyncProcessorHelper.process(AsyncProcessor, Exchange, AsyncCallback)

prepareExchangeForFailover

protected Exchange prepareExchangeForFailover(Exchange exchange)

Prepares the exchange for failover

Parameters:

exchange - the exchange

Returns:

a copy of the exchange to use for failover

toString

public String toString()

Overrides:

toString in class Object

getTraceLabel

public String getTraceLabel()

Description copied from interface: Traceable

Gets the trace label used for logging when tracing is enabled.

The label should be short and precise.

Specified by:

getTraceLabel in interface Traceable

Returns:

the label