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You can define a proxy in the spring XML file as shown below

{snippet:id=e1|lang=xml|url=camel/trunk/components/camel-spring/src/test/resources/org/apache/camel/spring/config/AnotherCamelProxyTest.xml}

{snippet:id=e1|lang=java|url=camel/trunk/components/camel-spring/src/test/java/org/apache/camel/spring/config/AnotherCamelProxyTest.java}

Proxy from Java

You can also create a proxy from regular Java using a org.apache.camel.component.bean.ProxyHelper as shown below:

    Endpoint endpoint = context.getEndpoint("direct:start");
    MyProxySender sender = ProxyHelper.createProxy(endpoint, MyProxySender.class);

In Camel 2.3 you can use org.apache.camel.builder.ProxyBuilder which may be easier to use than ProxyHelper:

{snippet:id=e4|lang=java|url=camel/trunk/camel-core/src/test/java/org/apache/camel/component/bean/BeanProxyTest.java}

Proxy with Annotation

Another way to configure the proxy from java is by using the @Produce annotation. Also see POJO Producing.

@Produce(uri="direct:start")
MyProxySender sender;

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When using a proxy Camel will send the message payload as a org.apache.camel.component.bean.BeanInvocation object which holds the details of which method was invoked and what the argument was.

From Camel 2.16 onwards you can enable binding which will use binding information from the method signature parameters to bind to the Exchange/Message with the following annotations

If a parameter does not have any annotation then the parameter is bound to the message body.

For example given the following interface

public interface MyAuditService {
    void auditMessage(@Header("uuid") String uuid, @Body String body);
}

Then from Java DSL we can create a proxy and call the method

// must enable binding on proxy
MyAuditService service = new ProxyBuilder(context).endpoint("jms:queue:foo").binding(true).build(MyAuditService.class);
service.auditMessage("1234", "Hello World");

Which will send the message to the JMS queue foo, with the header(uuid)=1234 and body=Hello World. The message is sent as InOnly as the method is void.

Turning the BeanInvocation into a first class payload

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If you proxied method signature only have one parameter such as:

String hello(String name);

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You can proxy Camel and let clients use the pure and clean interfaces as if Camel newer existed. Then Camel can proxy the invocation and receive the input passed into the single method parameter and regard that as if it was just the message payload.

Okay lets try that with an example

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At first we have the interface we wish to proxy

{snippet:id=e1|lang=java|url=camel/trunk/camel-core/src/test/java/org/apache/camel/component/bean/OrderService.java}

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Okay then we have the following route where we route using a Content Based Router that is XML based. See that we use XPath in the choices to route the message depending on its a book order or not.

{snippet:id=e1|lang=java|url=camel/trunk/camel-core/src/test/java/org/apache/camel/component/bean/BeanProxyTest.java}

{snippet:id=e2|lang=java|url=camel/trunk/camel-core/src/test/java/org/apache/camel/component/bean/BeanProxyTest.java}

{snippet:id=e3|lang=java|url=camel/trunk/camel-core/src/test/java/org/apache/camel/component/bean/BeanProxyTest.java}

Asynchronous using Future

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For example given this client interface

{snippet:id=e1|lang=java|title=Client Interface|url=camel/trunk/camel-core/src/test/java/org/apache/camel/component/bean/ProxyReturnFutureTest.java}

{snippet:id=e2|lang=java|title=Using Client|url=camel/trunk/camel-core/src/test/java/org/apache/camel/component/bean/ProxyReturnFutureTest.java}

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