Modified: websites/production/camel/content/wire-tap.html
==============================================================================
--- websites/production/camel/content/wire-tap.html (original)
+++ websites/production/camel/content/wire-tap.html Fri Mar 10 18:20:17 2017
@@ -86,7 +86,7 @@
<tbody>
<tr>
<td valign="top" width="100%">
-<div class="wiki-content maincontent"><h3 id="WireTap-WireTap">Wire
Tap</h3><p><a shape="rect" class="external-link"
href="http://www.enterpriseintegrationpatterns.com/WireTap.html";
rel="nofollow">Wire Tap</a> (from the <a shape="rect"
href="enterprise-integration-patterns.html">EIP patterns</a>) allows you to
route messages to a separate location while they are being forwarded to the
ultimate destination.</p><p><span class="confluence-embedded-file-wrapper"><img
class="confluence-embedded-image confluence-external-resource"
src="http://www.enterpriseintegrationpatterns.com/img/WireTap.gif";
data-image-src="http://www.enterpriseintegrationpatterns.com/img/WireTap.gif";></span></p><div
class="confluence-information-macro
confluence-information-macro-information"><p class="title">Streams</p><span
class="aui-icon aui-icon-small aui-iconfont-info
confluence-information-macro-icon"></span><div
class="confluence-information-macro-body"><p>If you <a shape="rect"
href="wire-tap.html">Wire Tap
</a> a stream message body then you should consider enabling <a shape="rect"
href="stream-caching.html">Stream caching</a> to ensure the message body can be
read at each endpoint. See more details at <a shape="rect"
href="stream-caching.html">Stream caching</a>.</p></div></div><h3
id="WireTap-Options">Options</h3><div class="table-wrap"><table
class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1"
class="confluenceTh"><p>Name</p></th><th colspan="1" rowspan="1"
class="confluenceTh"><p>Default Value</p></th><th colspan="1" rowspan="1"
class="confluenceTh"><p>Description</p></th></tr><tr><td colspan="1"
rowspan="1" class="confluenceTd"><p><code>uri</code></p></td><td colspan="1"
rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p><strong>Mandatory:</strong> The URI of the endpoint to
which the wire-tapped message will be sent. From <strong>Camel 2.16</strong>
onwards support dynamic to uris like documented in <a shape="rect" c
lass="external-link" href="http://camel.apache.org/message-endpoint.html";
style="line-height: 1.4285715;">Message Endpoint</a></p></td></tr><tr><td
colspan="1" rowspan="1"
class="confluenceTd"><p><code>executorServiceRef</code></p></td><td colspan="1"
rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p>Reference identifier of a custom <a shape="rect"
href="threading-model.html">Thread Pool</a> to use when processing the
wire-tapped messages. If not set, Camel will use a default thread
pool.</p></td></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><p><code>processorRef</code></p></td><td colspan="1"
rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p>Reference identifier of a custom <a shape="rect"
href="processor.html">Processor</a> to use for creating a new message (e.g.,
the "send a new message" mode). See below.</p></td></tr><tr><td colspan="1"
rowspan="1" class="conflue
nceTd"><p><code>copy</code></p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p><code>true</code></p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p><strong>Camel 2.3</strong>: Whether to copy the <a
shape="rect" href="exchange.html">Exchange</a> before wire-tapping the
message.</p></td></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><p><code>onPrepareRef</code></p></td><td colspan="1"
rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p><strong>Camel 2.8:</strong> Reference identifier of a
custom <a shape="rect" href="processor.html">Processor</a> to prepare the copy
of the <a shape="rect" href="exchange.html">Exchange</a> to be wire-tapped.
This allows you to do any custom logic, such as deep-cloning the message
payload.</p></td></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><code>cacheSize</code></td><td colspan="1" rowspan="1"
class="confluenceTd"> </td><td colspan="1" rowspan="1" class=
"confluenceTd"><span style="color: rgb(0,0,0);"><strong>Camel 2.16:</strong>
Allows to configure the cache size for
the </span><code>ProducerCache</code><span style="color:
rgb(0,0,0);"> which caches producers for reuse. Will by default use the
default cache size which is 1000. Setting the value to -1 allows to turn off
the cache all together.</span></td></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><code>ignoreInvalidEndpoint</code></td><td colspan="1"
rowspan="1" class="confluenceTd"><code>false</code></td><td colspan="1"
rowspan="1" class="confluenceTd"><strong>Camel 2.16:</strong> <span
style="color: rgb(0,0,0);">Whether to ignore an endpoint URI that could not be
resolved. If disabled, Camel will throw an exception identifying the invalid
endpoint URI.</span></td></tr></tbody></table></div><h3
id="WireTap-WireTapthreadpool">WireTap thread pool</h3><p>The <a shape="rect"
href="wire-tap.html">Wire Tap</a> uses a thread pool to process the tapped
messages. Th
is thread pool will by default use the settings detailed at <a shape="rect"
href="threading-model.html">Threading Model</a>. In particular, when the pool
is exhausted (with all threads utilized), further wiretaps will be executed
synchronously by the calling thread. To remedy this, you can configure an
explicit thread pool on the <a shape="rect" href="wire-tap.html">Wire Tap</a>
having either a different rejection policy, a larger worker queue, or more
worker threads.</p><h3 id="WireTap-WireTapnode">WireTap node</h3><p>Camel's
Wire Tap node supports two flavors when tapping an <a shape="rect"
href="exchange.html">Exchange</a>:</p><p>-With the traditional Wire Tap, Camel
will copy the original <a shape="rect" href="exchange.html">Exchange</a> and
set its <a shape="rect" href="exchange-pattern.html">Exchange Pattern</a> to
InOnly, as we want the tapped <a shape="rect" href="exchange.html">Exchange</a>
to be sent in a fire and forget style. The tapped <a shape="rect"
href="exchange.htm
l">Exchange</a> is then sent in a separate thread so it can run in parallel
with the original. Beware that only the Exchange is copied - Wire Tap won't do
a deep clone (unless you specify a custom processor via <em>onPrepareRef</em>
which does that). So all copies could share objects from the original
Exchange.</p><p>-Camel also provides an option of sending a new <a shape="rect"
href="exchange.html">Exchange</a> allowing you to populate it with new
values.</p><h4 id="WireTap-Sendingacopy(traditionalwiretap)">Sending a copy
(traditional wiretap)</h4><p><strong>Using the <a shape="rect"
href="fluent-builders.html">Fluent Builders</a></strong></p><div class="code
panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+<div class="wiki-content maincontent"><h3 id="WireTap-WireTap">Wire
Tap</h3><p><a shape="rect" class="external-link"
href="http://www.enterpriseintegrationpatterns.com/WireTap.html";
rel="nofollow">Wire Tap</a> (from the <a shape="rect"
href="enterprise-integration-patterns.html">EIP patterns</a>) allows you to
route messages to a separate location while they are being forwarded to the
ultimate destination.</p><p><span class="confluence-embedded-file-wrapper"><img
class="confluence-embedded-image confluence-external-resource"
src="http://www.enterpriseintegrationpatterns.com/img/WireTap.gif";
data-image-src="http://www.enterpriseintegrationpatterns.com/img/WireTap.gif";></span></p><div
class="confluence-information-macro
confluence-information-macro-information"><p class="title">Streams</p><span
class="aui-icon aui-icon-small aui-iconfont-info
confluence-information-macro-icon"></span><div
class="confluence-information-macro-body"><p>If you <a shape="rect"
href="wire-tap.html">Wire Tap
</a> a stream message body then you should consider enabling <a shape="rect"
href="stream-caching.html">Stream caching</a> to ensure the message body can be
read at each endpoint. See more details at <a shape="rect"
href="stream-caching.html">Stream caching</a>.</p></div></div><h3
id="WireTap-Options">Options</h3><div class="table-wrap"><table
class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1"
class="confluenceTh">Name</th><th colspan="1" rowspan="1"
class="confluenceTh"><p>Default</p></th><th colspan="1" rowspan="1"
class="confluenceTh"><p>Description</p></th></tr><tr><td colspan="1"
rowspan="1" class="confluenceTd"><p><code>uri</code></p></td><td colspan="1"
rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p><strong><span style="color:
rgb(255,0,0);">Mandatory</span>:</strong> The URI of the endpoint to which the
wire-tapped message should be sent.</p><p>From <strong>Camel 2.16</strong>:
support for dynamic <stro
ng><code>to</code></strong> URIs is as documented in <a shape="rect"
class="external-link" href="http://camel.apache.org/message-endpoint.html";
style="line-height: 1.4285715;">Message Endpoint.</a></p></td></tr><tr><td
colspan="1" rowspan="1"
class="confluenceTd"><p><code>executorServiceRef</code></p></td><td colspan="1"
rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p>Reference ID of a custom <a shape="rect"
href="threading-model.html">Thread Pool</a> to use when processing the
wire-tapped messages.</p><p>When not set, Camel will use an instance of the
default thread pool.</p></td></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><p><code>processorRef</code></p></td><td colspan="1"
rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p>Reference ID of a custom <a shape="rect"
href="processor.html">Processor</a> to use for creating a new
message.</p><p>See "<strong>Sending a
New Exchange</strong>" below.</p></td></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><p><code>copy</code></p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p><code>true</code></p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p><strong>Camel 2.3</strong>: Whether to copy the <a
shape="rect" href="exchange.html">Exchange</a> before wire-tapping the
message.</p></td></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><p><code>onPrepareRef</code></p></td><td colspan="1"
rowspan="1" class="confluenceTd"><p> </p></td><td colspan="1" rowspan="1"
class="confluenceTd"><p><strong>Camel 2.8:</strong> Reference identifier of a
custom <a shape="rect" href="processor.html">Processor</a> to prepare the copy
of the <a shape="rect" href="exchange.html">Exchange</a> to be wire-tapped.
This allows you to do any custom logic, such as deep-cloning the message
payload.</p></td></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><p><code>cacheSize</code></p></
td><td colspan="1" rowspan="1" class="confluenceTd"> </td><td colspan="1"
rowspan="1" class="confluenceTd"><p><span style="color:
rgb(0,0,0);"><strong>Camel 2.16:</strong> Allows to configure the cache size
for the </span><strong><code>ProducerCache</code></strong><span
style="color: rgb(0,0,0);"> which caches producers for reuse. Will by
default use the default cache size which is <strong><code>1000</code></strong>.
</span></p><p><span style="color: rgb(0,0,0);">Setting the value
to <strong><code>-1</code></strong> allows to turn off the cache all
together.</span></p></td></tr><tr><td colspan="1" rowspan="1"
class="confluenceTd"><p><code>ignoreInvalidEndpoint</code></p></td><td
colspan="1" rowspan="1" class="confluenceTd"><p><code>false</code></p></td><td
colspan="1" rowspan="1" class="confluenceTd"><p><strong>Camel 2.16:</strong>
<span style="color: rgb(0,0,0);">Whether to ignore an endpoint URI that could
not be resolved. </span></p><p><span style="color: rgb(
0,0,0);">When <strong><code>false</code></strong>, Camel will throw an
exception when it identifies an invalid endpoint
URI.</span></p></td></tr></tbody></table></div><h3
id="WireTap-WireTapThreadpool">WireTap Threadpool</h3><p>The <a shape="rect"
href="wire-tap.html">Wire Tap</a> uses a thread pool to process the tapped
messages. This thread pool will by default use the settings detailed at <a
shape="rect" href="threading-model.html">Threading Model</a>. In particular,
when the pool is exhausted (with all threads utilized), further wiretaps will
be executed synchronously by the calling thread. To remedy this, you can
configure an explicit thread pool on the <a shape="rect"
href="wire-tap.html">Wire Tap</a> having either a different rejection policy, a
larger worker queue, or more worker threads.</p><h3
id="WireTap-WireTapNode">WireTap Node</h3><p>Camel's Wire Tap node supports two
flavors when tapping an <a shape="rect"
href="exchange.html">Exchange</a>:</p><ul><li>With the traditi
onal Wire Tap, Camel will copy the original <a shape="rect"
href="exchange.html">Exchange</a> and set its <a shape="rect"
href="exchange-pattern.html">Exchange Pattern</a> to
<strong><code>InOnly</code></strong>, as we want the tapped <a shape="rect"
href="exchange.html">Exchange</a> to be sent in a fire and forget style. The
tapped <a shape="rect" href="exchange.html">Exchange</a> is then sent in a
separate thread so it can run in parallel with the original. Beware that only
the Exchange is copied - Wire Tap won't do a deep clone (unless you specify a
custom processor via <strong><code>onPrepareRef</code></strong> which does
that). So all copies could share objects from the original
Exchange.</li><li>Camel also provides an option of sending a new <a
shape="rect" href="exchange.html">Exchange</a> allowing you to populate it with
new values.</li></ul><h4 id="WireTap-SendingaCopy(traditionalwiretap)">Sending
a Copy (traditional wiretap)</h4><p><strong>Using the <a shape="rect" hr
ef="fluent-builders.html">Fluent Builders</a></strong></p><div class="code
panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: java; gutter: false; theme: Default"
type="syntaxhighlighter"><![CDATA[
from("direct:start")
.to("log:foo")
@@ -102,7 +102,7 @@ from("direct:start")
<to uri="mock:result"/>
</route>
]]></script>
-</div></div><h4 id="WireTap-Sendinganew">Sending a new <a shape="rect"
href="exchange.html">Exchange</a></h4><p><strong>Using the <a shape="rect"
href="fluent-builders.html">Fluent Builders</a></strong><br clear="none"> Camel
supports either a processor or an <a shape="rect"
href="expression.html">Expression</a> to populate the new <a shape="rect"
href="exchange.html">Exchange</a>. Using a processor gives you full power over
how the <a shape="rect" href="exchange.html">Exchange</a> is populated as you
can set properties, headers, et cetera. An <a shape="rect"
href="expression.html">Expression</a> can only be used to set the IN
body.</p><p>From <strong>Camel 2.3</strong> onwards the <a shape="rect"
href="expression.html">Expression</a> or <a shape="rect"
href="processor.html">Processor</a> is pre-populated with a copy of the
original <a shape="rect" href="exchange.html">Exchange</a>, which allows you to
access the original message when you prepare a new <a shape="rect"
href="exchange
.html">Exchange</a> to be sent. You can use the <code>copy</code> option
(enabled by default) to indicate whether you want this. If you set
<code>copy=false</code>, then it works as in Camel 2.2 or older where the <a
shape="rect" href="exchange.html">Exchange</a> will be empty.</p><p>Below is
the processor variation. This example is from Camel 2.3, where we disable
<code>copy</code> by passing in <code>false</code> to create a new, empty <a
shape="rect" href="exchange.html">Exchange</a>.</p><div class="code panel pdl"
style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><h4 id="WireTap-SendingaNew">Sending a New <a shape="rect"
href="exchange.html">Exchange</a></h4><p><strong>Using the <a shape="rect"
href="fluent-builders.html">Fluent Builders</a></strong><br clear="none"> Camel
supports either a processor or an <a shape="rect"
href="expression.html">Expression</a> to populate the new <a shape="rect"
href="exchange.html">Exchange</a>. Using a processor gives you full power over
how the <a shape="rect" href="exchange.html">Exchange</a> is populated as you
can set properties, headers, etc. An <a shape="rect"
href="expression.html">Expression</a> can only be used to set
the <strong><code>IN</code></strong> body.</p><p>From <strong>Camel
2.3</strong>: the <a shape="rect" href="expression.html">Expression</a> or <a
shape="rect" href="processor.html">Processor</a> is pre-populated with a copy
of the original <a shape="rect" href="exchange.html">Exchange</a>, which allows
you to access the original message when you prepare a new <a shape
="rect" href="exchange.html">Exchange</a> to be sent. You can use the
<strong><code>copy</code></strong> option (enabled by default) to indicate
whether you want this. If you set <strong><code>copy=false</code></strong>,
then it works as in <strong>Camel 2.2</strong> or older where the <a
shape="rect" href="exchange.html">Exchange</a> will be empty.</p><p>Below is
the processor variation. This example is from <strong>Camel 2.3</strong>, where
we disable <strong><code>copy</code></strong> by passing in
<strong><code>false</code></strong> to create a new, empty <a shape="rect"
href="exchange.html">Exchange</a>.</p><div class="code panel pdl"
style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: java; gutter: false; theme: Default"
type="syntaxhighlighter"><![CDATA[
from("direct:start")
.wireTap("direct:foo", false, new Processor() {
@@ -115,7 +115,7 @@ from("direct:start")
from("direct:foo").to("mock:foo");
]]></script>
-</div></div>Here is the <a shape="rect" href="expression.html">Expression</a>
variation. This example is from Camel 2.3, where we disable <code>copy</code>
by passing in <code>false</code> to create a new, empty <a shape="rect"
href="exchange.html">Exchange</a>.<div class="code panel pdl"
style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div>Here is the <a shape="rect" href="expression.html">Expression</a>
variation. In the following example we disable copying by setting
<strong><code>copy</code><code>=false</code></strong> which results in the
creation of a new, empty <a shape="rect" href="exchange.html">Exchange</a>.<div
class="code panel pdl" style="border-width: 1px;"><div class="codeContent
panelContent pdl">
<script class="brush: java; gutter: false; theme: Default"
type="syntaxhighlighter"><![CDATA[
from("direct:start")
.wireTap("direct:foo", false, constant("Bye World"))
@@ -123,7 +123,7 @@ from("direct:start")
from("direct:foo").to("mock:foo");
]]></script>
-</div></div><strong>Using the <a shape="rect"
href="spring-xml-extensions.html">Spring XML Extensions</a></strong><br
clear="none"> The processor variation, which uses a
<strong>processorRef</strong> attribute to refer to a Spring bean by ID:<div
class="code panel pdl" style="border-width: 1px;"><div class="codeContent
panelContent pdl">
+</div></div><strong>Using the <a shape="rect"
href="spring-xml-extensions.html">Spring XML Extensions</a></strong><br
clear="none"> The processor variation, which uses
a <strong><code>processorRef</code></strong> attribute to refer to a
Spring bean by ID:<div class="code panel pdl" style="border-width: 1px;"><div
class="codeContent panelContent pdl">
<script class="brush: xml; gutter: false; theme: Default"
type="syntaxhighlighter"><![CDATA[
<route>
<from uri="direct:start2"/>
@@ -131,7 +131,7 @@ from("direct:foo").to("mo
<to uri="mock:result"/>
</route>
]]></script>
-</div></div>Here is the <a shape="rect" href="expression.html">Expression</a>
variation, where the expression is defined in the <strong>body</strong>
tag:<div class="code panel pdl" style="border-width: 1px;"><div
class="codeContent panelContent pdl">
+</div></div>Here is the <a shape="rect" href="expression.html">Expression</a>
variation, where the expression is defined in
the <strong><code>body</code></strong> tag:<div class="code panel pdl"
style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: xml; gutter: false; theme: Default"
type="syntaxhighlighter"><![CDATA[
<route>
<from uri="direct:start"/>
@@ -141,7 +141,7 @@ from("direct:foo").to("mo
<to uri="mock:result"/>
</route>
]]></script>
-</div></div>This variation accesses the body of the original message and
creates a new <a shape="rect" href="exchange.html">Exchange</a> based on the <a
shape="rect" href="expression.html">Expression</a>. It will create a new
Exchange and have the body contain <code>"Bye ORIGINAL BODY MESSAGE
HERE"</code><div class="code panel pdl" style="border-width: 1px;"><div
class="codeContent panelContent pdl">
+</div></div>This variation accesses the body of the original message and
creates a new <a shape="rect" href="exchange.html">Exchange</a> based on the <a
shape="rect" href="expression.html">Expression</a>. It will create a new
Exchange and have the body contain <code>"<strong>Bye ORIGINAL BODY MESSAGE
HERE</strong>"</code><div class="code panel pdl" style="border-width:
1px;"><div class="codeContent panelContent pdl">
<script class="brush: xml; gutter: false; theme: Default"
type="syntaxhighlighter"><![CDATA[
<route>
<from uri="direct:start"/>
@@ -151,11 +151,11 @@ from("direct:foo").to("mo
<to uri="mock:result"/>
</route>
]]></script>
-</div></div><h4 id="WireTap-FurtherExample">Further Example</h4><p>For another
example of this pattern, refer to the <a shape="rect" class="external-link"
href="http://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/processor/WireTapTest.java";>wire
tap test case</a>.</p><h3 id="WireTap-UsingDynamicUris">Using Dynamic
Uris</h3><p><strong>Available as of Camel 2.16:</strong></p><p>For example to
wire tap to a dynamic uri, then it supports the same dynamic uris as documented
in <a shape="rect" href="message-endpoint.html">Message Endpoint</a>. For
example to wire tap to a JMS queue where the header ID is part of the queue
name</p><div class="code panel pdl" style="border-width: 1px;"><div
class="codeContent panelContent pdl">
+</div></div><h4 id="WireTap-FurtherExample">Further Example</h4><p>For another
example of this pattern, refer to the <a shape="rect" class="external-link"
href="http://svn.apache.org/repos/asf/camel/trunk/camel-core/src/test/java/org/apache/camel/processor/WireTapTest.java";>wire
tap test case</a>.</p><h3 id="WireTap-UsingDynamicURIs">Using Dynamic
URIs</h3><p><strong>Available as of Camel 2.16:</strong></p><p>For example to
wire tap to a dynamic URI, then it supports the same dynamic URIs as documented
in <a shape="rect" href="message-endpoint.html">Message Endpoint</a>. For
example to wire tap to a JMS queue where the header ID is part of the queue
name:</p><div class="code panel pdl" style="border-width: 1px;"><div
class="codeContent panelContent pdl">
<script class="brush: java; gutter: false; theme: Default"
type="syntaxhighlighter"><![CDATA[from("direct:start")
.wireTap("jms:queue:backup-${header.id}")
.to("bean:doSomething");]]></script>
-</div></div><p> </p><h3
id="WireTap-SendinganewandsetheadersinDSL">Sending a new <a shape="rect"
href="exchange.html">Exchange</a> and set headers in
DSL</h3><p><strong>Available as of Camel 2.8</strong></p><p>If you send a new
message using <a shape="rect" href="wire-tap.html">Wire Tap</a>, then you could
only set the message body using an <a shape="rect"
href="expression.html">Expression</a> from the DSL. If you also need to set
headers, you would have to use a <a shape="rect"
href="processor.html">Processor</a>. In Camel 2.8 onwards, you can now set
headers as well in the DSL.</p><p>The following example sends a new message
which has</p><ul class="alternate"><li>"Bye World" as message body</li><li>a
header with key "id" with the value 123</li><li>a header with key "date" which
has current date as value</li></ul><h4 id="WireTap-JavaDSL">Java
DSL</h4><p></p><div class="code panel pdl" style="border-width: 1px;"><div
class="codeContent panelContent pdl">
+</div></div><p> </p><h3
id="WireTap-SendingaNewandSetHeadersinDSL">Sending a New <a shape="rect"
href="exchange.html">Exchange</a> and Set Headers in
DSL</h3><p><strong>Available as of Camel 2.8</strong></p><p>If you send a new
message using <a shape="rect" href="wire-tap.html">Wire Tap</a>, then you could
only set the message body using an <a shape="rect"
href="expression.html">Expression</a> from the DSL. If you also need to set
headers, you would have to use a <a shape="rect"
href="processor.html">Processor</a>. From <strong>Camel 2.8</strong>: it's
possible to set headers as well using the DSL.</p><p>The following example
sends a new message which has</p><ul class="alternate"><li><strong><code>Bye
World</code></strong> as message body.</li><li>A header with
key <strong><code>id</code></strong> with the value
<strong><code>123</code></strong>.</li><li>A header with
key <strong><code>date</code></strong> which has current date as
value.</li></ul><h4 id="WireTap-Java
DSL">Java DSL</h4><p></p><div class="code panel pdl" style="border-width:
1px;"><div class="codeContent panelContent pdl">
<script class="brush: java; gutter: false; theme: Default"
type="syntaxhighlighter"><![CDATA[
from("direct:start")
// tap a new message and send it to direct:tap
@@ -173,7 +173,7 @@ from("direct:start")
from("direct:tap")
.to("mock:tap");
]]></script>
-</div></div><h4 id="WireTap-XMLDSL">XML DSL</h4><p>The XML DSL is slightly
different than Java DSL in how you configure the message body and headers using
<body> and <setHeader>:</p><div class="code panel pdl"
style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><h4 id="WireTap-XMLDSL">XML DSL</h4><p>The XML DSL is slightly
different than Java DSL in how you configure the message body and headers
using <strong><code><body></code></strong> and
<strong><code><setHeader></code></strong>:</p><div class="code panel pdl"
style="border-width: 1px;"><div class="codeContent panelContent pdl">
<script class="brush: xml; gutter: false; theme: Default"
type="syntaxhighlighter"><![CDATA[
<route>
<from uri="direct:start"/>
@@ -189,7 +189,7 @@ from("direct:tap")
<to uri="mock:result"/>
</route>
]]></script>
-</div></div><h3
id="WireTap-UsingonPreparetoexecutecustomlogicwhenpreparingmessages">Using
onPrepare to execute custom logic when preparing
messages</h3><p><strong>Available as of Camel 2.8</strong></p><p>See details at
<a shape="rect" href="multicast.html">Multicast</a></p><p></p><h4
id="WireTap-UsingThisPattern">Using This Pattern</h4>
+</div></div><h3
id="WireTap-UsingonPreparetoExecuteCustomLogicwhenPreparingMessages">Using <code>onPrepare</code>
to Execute Custom Logic when Preparing Messages</h3><p><strong>Available as of
Camel 2.8</strong></p><p>See details at <a shape="rect"
href="multicast.html">Multicast</a></p><p></p><h4
id="WireTap-UsingThisPattern">Using This Pattern</h4>
<p>If you would like to use this EIP Pattern then please read the <a
shape="rect" href="getting-started.html">Getting Started</a>, you may also find
the <a shape="rect" href="architecture.html">Architecture</a> useful
particularly the description of <a shape="rect"
href="endpoint.html">Endpoint</a> and <a shape="rect"
href="uris.html">URIs</a>. Then you could try out some of the <a shape="rect"
href="examples.html">Examples</a> first before trying this pattern
out.</p></div>
</td>
![http://www.enterpriseintegrationpatterns.com/img/WireTap.gif"](http://www.enterpriseintegrationpatterns.com/img/WireTap.gif"){kind=link}
