org.apache.camel.impl

Class LimitedPollingConsumerPollStrategy

java.lang.Object

org.apache.camel.impl.DefaultPollingConsumerPollStrategy

org.apache.camel.impl.LimitedPollingConsumerPollStrategy

All Implemented Interfaces:

Service, PollingConsumerPollStrategy

public class LimitedPollingConsumerPollStrategy
extends DefaultPollingConsumerPollStrategy
implements Service

A PollingConsumerPollStrategy which supports suspending consumers if they failed for X number of times in a row.

If Camel cannot successfully consumer from a given consumer, then after X consecutive failed attempts the consumer will be suspended/stopped. This prevents the log to get flooded with failed attempts, for example during nightly runs.

Version:

Field Summary

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

log

Constructor Summary

Constructors

Constructor and Description
LimitedPollingConsumerPollStrategy()

Method Summary

Methods

Modifier and Type	Method and Description
void	commit(Consumer consumer, Endpoint endpoint, int polledMessages) Called when poll is completed successfully
int	getLimit()
protected boolean	onRollback(Consumer consumer, Endpoint endpoint) Rollback occurred.
protected void	onSuspend(Consumer consumer, Endpoint endpoint) The consumer is to be suspended because it exceeded the limit
boolean	rollback(Consumer consumer, Endpoint endpoint, int retryCounter, Exception cause) Called when poll failed
void	setLimit(int limit) Sets the limit for how many straight rollbacks causes this strategy to suspend the fault consumer.
void	start() Starts the service
void	stop() Stops the service

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

begin

Methods inherited from class java.lang.Object

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

Constructor Detail

LimitedPollingConsumerPollStrategy

public LimitedPollingConsumerPollStrategy()

Method Detail

getLimit

public int getLimit()

setLimit

public void setLimit(int limit)

Sets the limit for how many straight rollbacks causes this strategy to suspend the fault consumer.

When the consumer has been suspended, it has to be manually resumed/started to be active again. The limit is by default 3.

Parameters:

limit - the limit

commit

public void commit(Consumer consumer,
          Endpoint endpoint,
          int polledMessages)

Description copied from interface: PollingConsumerPollStrategy

Called when poll is completed successfully

Specified by:

commit in interface PollingConsumerPollStrategy

Overrides:

commit in class DefaultPollingConsumerPollStrategy

Parameters:

consumer - the consumer

endpoint - the endpoint being consumed

polledMessages - number of messages polled, will be 0 if no message was polled at all.

rollback

public boolean rollback(Consumer consumer,
               Endpoint endpoint,
               int retryCounter,
               Exception cause)
                 throws Exception

Description copied from interface: PollingConsumerPollStrategy

Called when poll failed

Specified by:

rollback in interface PollingConsumerPollStrategy

Overrides:

rollback in class DefaultPollingConsumerPollStrategy

Parameters:

consumer - the consumer

endpoint - the endpoint being consumed

retryCounter - current retry attempt, starting from 0.

cause - the caused exception

Returns:

whether to retry immediately or not. Return false to ignore the problem, true to try immediately again

Throws:

Exception - can be used to rethrow the caused exception. Notice that thrown an exception will terminate the scheduler and thus Camel will not trigger again. So if you want to let the scheduler to continue to run then do not throw any exception from this method.

onSuspend

protected void onSuspend(Consumer consumer,
             Endpoint endpoint)
                  throws Exception

The consumer is to be suspended because it exceeded the limit

Parameters:

consumer - the consumer

endpoint - the endpoint

Throws:

Exception - is thrown if error suspending the consumer

onRollback

protected boolean onRollback(Consumer consumer,
                 Endpoint endpoint)
                      throws Exception

Rollback occurred.

Parameters:

consumer - the consumer

endpoint - the endpoint

Returns:

whether or not to retry immediately, is default false

Throws:

Exception - can be thrown in case something goes wrong

start

public void start()
           throws Exception

Description copied from interface: Service

Starts the service

Specified by:

start in interface Service

Throws:

Exception - is thrown if starting failed

stop

public void stop()
          throws Exception

Description copied from interface: Service

Stops the service

Specified by:

stop in interface Service

Throws:

Exception - is thrown if stopping failed