org.apache.camel.processor
Class Throttler

java.lang.Object
  org.apache.camel.support.ServiceSupport
      org.apache.camel.processor.DelegateAsyncProcessor
          org.apache.camel.processor.DelayProcessorSupport
              org.apache.camel.processor.Throttler

All Implemented Interfaces:

AsyncProcessor, DelegateProcessor, Navigate<Processor>, Processor, Service, ShutdownableService, StatefulService, SuspendableService, Traceable

public class Throttler
extends DelayProcessorSupport
implements Traceable

A Throttler will set a limit on the maximum number of message exchanges which can be sent to a processor within a specific time period.

This pattern can be extremely useful if you have some external system which meters access; such as only allowing 100 requests per second; or if huge load can cause a particular system to malfunction or to reduce its throughput you might want to introduce some throttling.

Version:

Nested Class Summary

protected class

Throttler.TimeSlot

Field Summary

Fields inherited from class org.apache.camel.processor.DelayProcessorSupport

log

Fields inherited from class org.apache.camel.processor.DelegateAsyncProcessor

processor

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

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

Constructor Summary

Throttler(CamelContext camelContext, Processor processor, Expression maxRequestsPerPeriodExpression, long timePeriodMillis, ScheduledExecutorService executorService, boolean shutdownExecutorService)

Method Summary

protected long	calculateDelay(Exchange exchange)
long	getCurrentMaximumRequestsPerPeriod() Gets the current maximum request per period value.
Expression	getMaximumRequestsPerPeriodExpression()
long	getTimePeriodMillis()
String	getTraceLabel() Gets the trace label used for logging when tracing is enabled.
protected Throttler.TimeSlot	nextSlot()
void	setMaximumRequestsPerPeriodExpression(Expression maxRequestsPerPeriodExpression) Sets the maximum number of requests per time period expression
void	setTimePeriodMillis(long timePeriodMillis) Sets the time period during which the maximum number of requests apply
String	toString()

Methods inherited from class org.apache.camel.processor.DelayProcessorSupport

currentSystemTime, delay, doShutdown, doStart, handleSleepInterruptedException, isAsyncDelayed, isCallerRunsWhenRejected, process, setAsyncDelayed, setCallerRunsWhenRejected

Methods inherited from class org.apache.camel.processor.DelegateAsyncProcessor

doStop, getProcessor, hasNext, next, process, processNext, setProcessor, setProcessor

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

doResume, doSuspend, getStatus, getVersion, isRunAllowed, 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

Throttler

public Throttler(CamelContext camelContext,
                 Processor processor,
                 Expression maxRequestsPerPeriodExpression,
                 long timePeriodMillis,
                 ScheduledExecutorService executorService,
                 boolean shutdownExecutorService)

Method Detail

toString

public String toString()

Overrides:

toString in class DelegateAsyncProcessor

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

setMaximumRequestsPerPeriodExpression

public void setMaximumRequestsPerPeriodExpression(Expression maxRequestsPerPeriodExpression)

Sets the maximum number of requests per time period expression

getMaximumRequestsPerPeriodExpression

public Expression getMaximumRequestsPerPeriodExpression()

getTimePeriodMillis

public long getTimePeriodMillis()

getCurrentMaximumRequestsPerPeriod

public long getCurrentMaximumRequestsPerPeriod()

Gets the current maximum request per period value.

setTimePeriodMillis

public void setTimePeriodMillis(long timePeriodMillis)

Sets the time period during which the maximum number of requests apply

calculateDelay

protected long calculateDelay(Exchange exchange)

Specified by:

calculateDelay in class DelayProcessorSupport

nextSlot

protected Throttler.TimeSlot nextSlot()