Cant have a Map payload via payload-expression on a Gateway

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My intention is to have the service interface free from Spring dependencies and have all gateways defined on the context xml. Im getting

Ambiguous method parameters; found more than one Map-typed parameter and neither one contains a @Payload annotation

Is this intentional and is there any work around?


Thanks!

[Cleric]

Hello

Please, read this one: http://static.springsource.org/sprin...r.html#gateway
And keep in mind: if your gateway's method has more then one parameters you should say to framework which from them to interpret as payload and which as headers

And as you see the exception asks you to add that one ;-)

Cheers,
Artem Bilan

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Hi Cleric,

Thank you for your response.

What I was actually doing is specify via XML configuration (payload-expression) what the payload should be. Here is a sample:

public interface CampaignGateway {

	public Campaign createCampaign(Map<String, String> map);
}

on the gateway definition

 <int:gateway service-interface="my.integration.CampaignGateway">
         <int:method name="createCampaign"  request-channel="requestChannel" 
                      payload-expression="#args[0]" reply-channel="responseChannel">
                     <int:header name="Content-type" value="application/x-www-form-urlencoded"/>
         </int:method>
     </int:gateway>

Please note that I use payload-expression="#args[0]".

Im getting mbiguous method parameters; found more than one Map-typed parameter and neither one contains a @Payload annotation.

Checking GatewayMethodInboundMessageMapper, here's the code that throws the exception:

      else if (Map.class.isAssignableFrom(methodParameter.getParameterType())) {
				if (messageOrPayload instanceof Map && !foundPayloadAnnotation) {
					throw new MessagingException("Ambiguous method parameters; found more than one " +
							"Map-typed parameter and neither one contains a @Payload annotation");
				}
				this.copyHeaders((Map<?, ?>) argumentValue, headers);
			}

It seems the code only expects Map type payloads to be defined via @Payload annotation.

Thanks!

[Cleric]

A-ha!

Now I understand you!
Great catch!
I've just reproduced it:

@Test
	public void toMessageWithMap() throws Exception {
		Method method = TestService.class.getMethod("sendMap", Map.class);
		GatewayMethodInboundMessageMapper mapper = new GatewayMethodInboundMessageMapper(method);
		mapper.setPayloadExpression("#args[0]");
		Message<?> message = mapper.toMessage(new Object[] {new HashMap<String, String>()});
		assertEquals("test", message.getPayload());
	}

It's realy a bug.
Can you open a JIRA about this and we will think what to do: https://jira.springsource.org/browse/INT ?

Right now it sounds as "Can't use gateway's method parameter as Map and payload-expression together"

Thanks!

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Thanks Artem,

issue: https://jira.springsource.org/browse/INT-2613