EJB Component
Available as of Camel 2.4
The ejb: component binds EJBs to Camel message exchanges.
Maven users will need to add the following dependency to their pom.xml for this component:
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<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-ejb</artifactId>
<version>x.x.x</version>
<!-- use the same version as your Camel core version -->
</dependency>
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ejb:ejbName[?options]
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Where ejbName can be any string which is used to look up the EJB in the Application Server JNDI Registry
Options
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Name | Type | Default | Description |
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method | String | null | The method name that bean will be invoked. If not provided, Camel will try to pick the method itself. In case of ambiguity an exception is thrown. See Bean Binding for more details. | multiParameterArray | boolean | false | How to treat the parameters which are passed from the message body; if it is true, the In message body should be an array of parameters. |
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You can append query options to the URI in the following format, ?option=value&option=value&...
The EJB component extends the Bean component in which most of the details from the Bean component applies to this component as well.
Bean Binding
How bean methods to be invoked are chosen (if they are not specified explicitly through the method parameter) and how parameter values are constructed from the Message are all defined by the Bean Binding mechanism which is used throughout all of the various Bean Integration mechanisms in Camel.
Examples
In the following examples we use the Greater EJB which is defined as follows:
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{snippet:id=e1|lang=java|title=GreaterLocal.java|url=camel/trunk/components/camel-ejb/src/test/java/org/apache/camel/component/ejb/GreaterLocal.java} |
And the implementation
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{snippet:id=e1|lang=java|title=GreaterImpl.java|url=camel/trunk/components/camel-ejb/src/test/java/org/apache/camel/component/ejb/GreaterImpl.java} |
Using Java DSL
In this example we want to invoke the hello method on the EJB. Since this example is based on an unit test using Apache OpenEJB we have to set a JndiContext on the EJB component with the OpenEJB settings.
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{snippet:id=e1|lang=java|url=camel/trunk/components/camel-ejb/src/test/java/org/apache/camel/component/ejb/GreaterCamelEjbTest.java} |
Then we are ready to use the EJB in the Camel route:
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{snippet:id=e2|lang=java|url=camel/trunk/components/camel-ejb/src/test/java/org/apache/camel/component/ejb/GreaterCamelEjbTest.java} |
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| title | In a real application server |
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In a real application server you most likely do not have to setup a JndiContext on the EJB component as it will create a default JndiContext on the same JVM as the application server, which usually allows it to access the JNDI registry and lookup the EJBs.
However if you need to access a application server on a remote JVM or the likes, you have to prepare the properties beforehand. |
Using Spring XML
And this is the same example using Spring XML instead:
Again since this is based on an unit test we need to setup the EJB component:
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{snippet:id=e1|lang=xml|url=camel/trunk/components/camel-ejb/src/test/resources/org/apache/camel/component/ejb/SpringGreaterCamelEjbTest.xml} |
Before we are ready to use EJB in the Camel routes:
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{snippet:id=e2|lang=xml|url=camel/trunk/components/camel-ejb/src/test/resources/org/apache/camel/component/ejb/SpringGreaterCamelEjbTest.xml} |
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| Endpoint See Also |
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| Endpoint See Also |
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