org.apache.camel.impl

Class EventDrivenPollingConsumer

java.lang.Object

org.apache.camel.support.ServiceSupport

org.apache.camel.impl.PollingConsumerSupport

org.apache.camel.impl.EventDrivenPollingConsumer

All Implemented Interfaces:

Consumer, PollingConsumer, Processor, Service, ShutdownableService, StatefulService, SuspendableService

public class EventDrivenPollingConsumer
extends PollingConsumerSupport
implements Processor

A default implementation of the PollingConsumer which uses the normal asynchronous consumer mechanism along with a BlockingQueue to allow the caller to pull messages on demand.

Version:

Field Summary

Fields inherited from class org.apache.camel.impl.PollingConsumerSupport

log

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

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

Constructor Summary

Constructors

Constructor and Description
EventDrivenPollingConsumer(Endpoint endpoint)
EventDrivenPollingConsumer(Endpoint endpoint, BlockingQueue<Exchange> queue)
EventDrivenPollingConsumer(Endpoint endpoint, int queueSize)

Method Summary

Methods

Modifier and Type	Method and Description
protected void	afterPoll()
protected long	beforePoll(long timeout)
protected void	doShutdown() Implementations override this method to perform customized shutdown.
protected void	doStart() Implementations override this method to support customized start/stop.
protected void	doStop() Implementations override this method to support customized start/stop.
ExceptionHandler	getInterruptedExceptionHandler()
int	getQueueCapacity() Gets the queue capacity.
int	getQueueSize() Gets the current queue size (no of elements in the queue).
protected void	handleInterruptedException(InterruptedException e)
boolean	isBlockWhenFull()
void	process(Exchange exchange) Processes the message exchange
Exchange	receive() Waits until a message is available and then returns it.
Exchange	receive(long timeout) Attempts to receive a message exchange, waiting up to the given timeout to expire if a message is not yet available.
Exchange	receiveNoWait() Attempts to receive a message exchange immediately without waiting and returning null if a message exchange is not available yet.
void	setBlockWhenFull(boolean blockWhenFull)
void	setInterruptedExceptionHandler(ExceptionHandler interruptedExceptionHandler)

Methods inherited from class org.apache.camel.impl.PollingConsumerSupport

getEndpoint, getExceptionHandler, handleException, setExceptionHandler, toString

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

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

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.camel.Service

start, stop

Constructor Detail

EventDrivenPollingConsumer

public EventDrivenPollingConsumer(Endpoint endpoint)

EventDrivenPollingConsumer

public EventDrivenPollingConsumer(Endpoint endpoint,
                          int queueSize)

EventDrivenPollingConsumer

public EventDrivenPollingConsumer(Endpoint endpoint,
                          BlockingQueue<Exchange> queue)

Method Detail

isBlockWhenFull

public boolean isBlockWhenFull()

setBlockWhenFull

public void setBlockWhenFull(boolean blockWhenFull)

getQueueCapacity

public int getQueueCapacity()

Gets the queue capacity.

getQueueSize

public int getQueueSize()

Gets the current queue size (no of elements in the queue).

receiveNoWait

public Exchange receiveNoWait()

Description copied from interface: PollingConsumer

Attempts to receive a message exchange immediately without waiting and returning null if a message exchange is not available yet.

Important: See the class javadoc about the need for done the UnitOfWork on the returned Exchange

Specified by:

receiveNoWait in interface PollingConsumer

Returns:

the message exchange if one is immediately available otherwise null

receive

public Exchange receive()

Description copied from interface: PollingConsumer

Waits until a message is available and then returns it. Warning that this method could block indefinitely if no messages are available.

Will return null if the consumer is not started

Important: See the class javadoc about the need for done the UnitOfWork on the returned Exchange

Specified by:

receive in interface PollingConsumer

Returns:

the message exchange received.

receive

public Exchange receive(long timeout)

Description copied from interface: PollingConsumer

Attempts to receive a message exchange, waiting up to the given timeout to expire if a message is not yet available.

Important: See the class javadoc about the need for done the UnitOfWork on the returned Exchange

Specified by:

receive in interface PollingConsumer

Parameters:

timeout - the amount of time in milliseconds to wait for a message before timing out and returning null

Returns:

the message exchange if one iwas available within the timeout period, or null if the timeout expired

process

public void process(Exchange exchange)
             throws Exception

Description copied from interface: Processor

Processes the message exchange

Specified by:

process in interface Processor

Parameters:

exchange - the message exchange

Throws:

Exception - if an internal processing error has occurred.

getInterruptedExceptionHandler

public ExceptionHandler getInterruptedExceptionHandler()

setInterruptedExceptionHandler

public void setInterruptedExceptionHandler(ExceptionHandler interruptedExceptionHandler)

handleInterruptedException

protected void handleInterruptedException(InterruptedException e)

beforePoll

protected long beforePoll(long timeout)

afterPoll

protected void afterPoll()

doStart

protected void doStart()
                throws Exception

Description copied from class: ServiceSupport

Implementations override this method to support customized start/stop.

Important: See ServiceSupport.doStop() for more details.

Specified by:

doStart in class ServiceSupport

Throws:

Exception

See Also:

ServiceSupport.doStop()

doStop

protected void doStop()
               throws Exception

Description copied from class: ServiceSupport

Implementations override this method to support customized start/stop.

Important: Camel will invoke this ServiceSupport.doStop() method when the service is being stopped. This method will also be invoked if the service is still in uninitialized state (eg has not been started). The method is always called to allow the service to do custom logic when the service is being stopped, such as when CamelContext is shutting down.

Specified by:

doStop in class ServiceSupport

Throws:

Exception

See Also:

ServiceSupport.doStart()

doShutdown

protected void doShutdown()
                   throws Exception

Description copied from class: ServiceSupport

Implementations override this method to perform customized shutdown.

Overrides:

doShutdown in class ServiceSupport

Throws:

Exception