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h2. NMR Component

The *nmr* component is an adapter to the Normalized Message Router (NMR) in [ServiceMix|http://servicemix.apache.org/home.html], which is intended for use by Camel applications deployed directly into the OSGi container. By contrast, the [JBI] component is intended for use by Camel applications deployed into the ServiceMix JBI container.

h3. Installing

The NMR component is provided with Apache ServiceMix. It is *not* distributed with Camel. To install the NMR component in ServiceMix, enter the following command in the ServiceMix console window:

{code}
features install nmr
{code}

You also need to instantiate the NMR component. You can do this by editing your Spring configuration file, {{META-INF/spring/*.xml}}, and adding the following {{bean}} instance:

{code:xml}
<beans xmlns:osgi="http://www.springframework.org/schema/osgi" ... >
    ...
    <bean id="nmr" class="org.apache.servicemix.camel.nmr.ServiceMixComponent">
        <property name="nmr">
            <osgi:reference interface="org.apache.servicemix.nmr.api.NMR" />
        </property>
    </bean>
    ...
</beans>
{code}

h3. NMR consumer and producer endpoints

The following code:

{code}
from("nmr:MyServiceEndpoint")
{code}

Automatically exposes a new endpoint to the bus with endpoint name {{MyServiceEndpoint}} (see [#URI-format]).

When an NMR endpoint appears at the end of a route, for example:

{code}
to("nmr:MyServiceEndpoint")
{code}

The messages sent by this producer endpoint are sent to the already deployed JBI endpoint.

{anchor:URI-format}
h3. URI format

{code}
nmr:endpointName
{code}

h4. URI Options
{div:class=confluenceTableSmall}
|| Option || Default Value || Description ||
| {{runAsSubject}} | {{false}} | When this is set to *{{true}}* on a consumer endpoint, the endpoint will be invoked on behalf of the {{Subject}} that is set on the {{Exchange}} (i.e. the call to {{Subject.getSubject(AccessControlContext)}} will return the {{Subject}} instance) |
| {{synchronous}} | {{false}} | When this is set to *{{true}}* on a consumer endpoint, an incoming, synchronous NMR Exchange will be handled on the sender's thread instead of being handled on a new thread of the NMR endpoint's thread pool |
| {{timeout}} | {{0}} | When this is set to a value greater than 0, the producer endpoint will timeout if it doesn't receive a response from the NMR within the given timeout period (in milliseconds).  Configuring a timeout value will switch to using synchronous interactions with the NMR instead of the usual asynchronous messaging. |
{div}

h4. Examples

{code}
from("nmr:MyServiceEndpoint")
from("nmr:MyServiceEndpoint?synchronous=true").to("nmr:AnotherEndpoint")
{code}

h3. Using Stream bodies
If you are using a stream type as the message body, you should be aware that a stream is only capable of being read once. So if you enable {{DEBUG}} logging, the body is usually logged and thus read. To deal with this, Camel has a {{streamCaching}} option that can cache the stream, enabling you to read it multiple times.

{code}
from("nmr:MyEndpoint").streamCaching().to("xslt:transform.xsl", "bean:doSomething");
{code}

From *Camel 1.5* onwards, the stream caching is default enabled, so it is not necessary to set the {{streamCaching()}} option.
In *Camel 2.0* we store big input streams (by default, over 64K) in a {{temp}} file using {{CachedOutputStream}}. When you close the input stream, the temp file will be deleted.

{include:Endpoint See Also}