Message Endpoint

Camel supports the Message Endpoint from the EIP patterns using the Endpoint interface.

When using the DSL to create Routes you typically refer to Message Endpoints by their URIs rather than directly using the Endpoint interface. Its then a responsibility of the CamelContext to create and activate the necessary Endpoint instances using the available Component implementations.

Example

The following example route demonstrates the use of a File Consumer Endpoint and JMS Producer Endpoint


Using the Fluent Builders

from("file://local/router/messages/foo")
	.to("jms:queue:foo");

 

Using the Spring XML Extensions

<route>
	<from uri="file://local/router/messages/foo"/>
	<to uri="jms:queue:foo"/>
</route>

 

Dynamic To

Available as of Camel 2.16

There is a new <toD> that allows to send a message to a dynamic computed Endpoint using one or more Expression that are concat together. By default the Simple language is used to compute the endpoint. For example to send a message to a endpoint defined by a header you can do

<route>
  <from uri="direct:start"/>
  <toD uri="${header.foo}"/>
</route>

And in Java DSL

from("direct:start")
  .toD("${header.foo}");

 

You can also prefix the uri with a value because by default the uri is evaluated using the Simple language

<route>
  <from uri="direct:start"/>
  <toD uri="mock:${header.foo}"/>
</route>

And in Java DSL

from("direct:start")
  .toD("mock:${header.foo}");

In the example above we compute an endpoint that has prefix "mock:" and then the header foo is appended. So for example if the header foo has value order, then the endpoint is computed as "mock:order".

You can also use other languages than Simple such as XPath - this requires to prefix with language: as shown below (simple language is the default language). If you do not specify language: then the endpoint is a component name. And in some cases there is both a component and language with the same name such as xquery.

<route>
  <from uri="direct:start"/>
  <toD uri="language:xpath:/order/@uri"/>
</route>

This is done by specifying the name of the language followed by a colon.

from("direct:start")
  .toD("language:xpath:/order/@uri");

You can also concat multiple Language(s) together using the plus sign + such as shown below:

<route>
  <from uri="direct:start"/>
  <toD uri="jms:${header.base}+language:xpath:/order/@id"/>
</route>

In the example above the uri is a combination of Simple language and XPath where the first part is simple (simple is default language). And then the plus sign separate to another language, where we specify the language name followed by a colon

from("direct:start")
  .toD("jms:${header.base}+language:xpath:/order/@id");

You can concat as many languages as you want, just separate them with the plus sign

The Dynamic To has a few options you can configure

NameDefault ValueDescription
uri Mandatory: The uri to use. See above
pattern To set a specific Exchange Pattern to use when sending to the endpoint. The original MEP is restored afterwards.
cacheSize Allows to configure the cache size for the ProducerCache 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.
ignoreInvalidEndpointfalseWhether to ignore an endpoint URI that could not be resolved. If disabled, Camel will throw an exception identifying the invalid endpoint URI.

 

For more details see

Using This Pattern

If you would like to use this EIP Pattern then please read the Getting Started, you may also find the Architecture useful particularly the description of Endpoint and URIs. Then you could try out some of the Examples first before trying this pattern out.

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