How do I use Spring Property Placeholder with Camel XML
We do NOT yet support the ${something}
notation inside arbitrary
Camel XML. For example at the time of writing this is NOT supported
(due Spring limitations).
IS NOT SUPPORTED
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
http://activemq.apache.org/camel/schema/spring http://activemq.apache.org/camel/schema/spring/camel-spring.xsd
">
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"/>
<camelContext xmlns="http://activemq.apache.org/camel/schema/spring">
<route>
<from uri="activemq:${someQueueName}"/>
<to uri="mock:results"/>
</route>
</camelContext>
</beans>
However you can use the <endpoint/>
element to define endpoints which
does support the property resolving which you can then refer to by name,
using the Ref component as shown below (notice the ref:
in the URI):
SUPPORTED
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
http://activemq.apache.org/camel/schema/spring http://activemq.apache.org/camel/schema/spring/camel-spring.xsd
">
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"/>
<camelContext xmlns="http://activemq.apache.org/camel/schema/spring">
<endpoint id="input1" uri="activemq:${someQueueName}"/>
<route>
<from uri="ref:input1"/>
<to uri="activemq:OutputQueue"/>
</route>
</camelContext>
</beans>
Camel does not yet fully support property placeholders as there is a limitation in Spring. See JIRA SPR-4466
Bridge Spring and Camel property placeholders
From Camel 2.10 onwards you can bridge Spring and Camel property placeholders, see Using PropertyPlaceholder for more details.
Here is a trick that you can use to define the uri in a property file using Spring injection and Camel endpoint: http://cmoulliard.blogspot.com/2009/05/trick-to-pass-uri-declared-in-property.html.
From Camel 2.3 onwards there is a Properties component build in Camel core which allows you to use properties in the same way as Spring property placeholders, and even more.