THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
Throttler
The Throttler Pattern allows you to ensure that a specific endpoint does not get overloaded, or that we don't exceed an agreed SLA with some external service.
Options
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h3. Throttler The Throttler Pattern allows you to ensure that a specific endpoint does not get overloaded, or that we don't exceed an agreed SLA with some external service. h3. Options {div:class=confluenceTableSmall} || Name || Default Value || Description || | {{maximumRequestsPerPeriod}} | | Maximum number of requests per period to throttle. This option must be provided as a positive number. Notice, in the XML DSL, from *Camel 2.8* onwards this option is configured using an [Expression] instead of an attribute. | | {{timePeriodMillis}} | {{1000}} | The time period in milliseconds, in which the throttler will allow at most {{maximumRequestsPerPeriod}} number of messages. | | {{asyncDelayed}} | {{false}} | *Camel 2.4:* If enabled then any messages which is delayed happens asynchronously using a scheduled thread pool. | | {{executorServiceRef}} | | *Camel 2.4:* Refers to a custom [Thread Pool|Threading Model] to be used if {{asyncDelay}} has been enabled. | | {{callerRunsWhenRejected}} | {{true}} | *Camel 2.4:* Is used if {{asyncDelayed}} was enabled. This controls if the caller thread should execute the task if the thread pool rejected the task. | {div} h3. Examples *Using the [Fluent Builders]* |
Examples
Using the Fluent Builders
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{snippet:id=ex|lang=java|url=camel/trunk/camel-core/src/test/java/org/apache/camel/processor/ThrottlerTest.java}
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So
...
the
...
above
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example
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will
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throttle
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messages
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all
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messages
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received
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on
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seda:a
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before
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being
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sent
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to
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mock:result
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ensuring
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that
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a
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maximum
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of
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3
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messages
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are
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sent
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in
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any
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10
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second
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window.
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Note
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that
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since
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timePeriodMillis
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defaults
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to
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1000
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milliseconds,
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just
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setting
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the
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maximumRequestsPerPeriod
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has
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the
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effect
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of
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setting
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the
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maximum
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number
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of
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requests
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per
...
second.
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So
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to
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throttle
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requests
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at
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100
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requests
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per
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second
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between
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two
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endpoints,
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it
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would
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look
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more
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like
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this...
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} from("seda:a").throttle(100).to("seda:b"); {code} |
For
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further
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examples
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of
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this
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pattern
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in
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use
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you
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could
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look
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at
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the
...
...
...
Using the Spring XML Extensions
Camel 2.7.x
...
or older
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older {snippet:id=example|lang=xml|url=camel/tags/camel-2.7.0/components/camel-spring/src/test/resources/org/apache/camel/spring/processor/throttler.xml} h4. |
Camel
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2.8
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onwards
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In
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Camel
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2.8
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onwards
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you
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must
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set
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the
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maximum
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period
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as
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an
...
...
as
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shown
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below
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where
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we
...
use
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a
...
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expression:
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{snippet:id=example|lang=xml|url=camel/trunk/components/camel-spring/src/test/resources/org/apache/camel/spring/processor/throttler.xml} h3. |
Dynamically
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changing
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maximum
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requests
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per
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period
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Available
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as
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of
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Camel
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2.8
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Since
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we
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use
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an
...
...
you
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can
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adjust
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this
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value
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at
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runtime,
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for
...
example
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you
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can
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provide
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a
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header
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with
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the
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value.
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At
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runtime
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Camel
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evaluates
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the
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expression
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and
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converts
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the
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result
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to
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a
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java.lang.Long
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type.
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In
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the
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example
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below
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we
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use
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a
...
header
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from
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the
...
message
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to
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determine
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the
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maximum
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requests
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per
...
period.
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If
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the
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header
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is
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absent,
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then
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the
...
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uses
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the
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old
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value.
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So
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that
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allows
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you
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to
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only
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provide
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a
...
header
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if
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the
...
value
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is
...
to
...
be
...
changed:
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{snippet:id=e2|lang=xml|url=camel/trunk/components/camel-spring/src/test/resources/org/apache/camel/spring/processor/throttler.xml} h3. |
Asynchronous
...
delaying
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Available
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as
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of
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Camel
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2.4
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You
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can
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let
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the
...
...
use
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non
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blocking
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asynchronous
...
delaying,
...
which
...
means
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Camel
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will
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use
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a
...
scheduler
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to
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schedule
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a
...
task
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to
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be
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executed
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in
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the
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future.
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The
...
task
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will
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then
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continue
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routing.
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This
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allows
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the
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caller
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thread
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to
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not
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block
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and
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be
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able
...
to
...
service
...
other
...
messages,
...
etc.
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} from("seda:a").throttle(100).asyncDelayed().to("seda:b"); {code} {include:Using This Pattern} |
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