EAI: Content Based Filter with Spring Integration

[opatopa]

Hi there,

I am trying to implement simple content based router using Spring integration and cannot figure out what should be the right way.

Case
On input channel I receive a simple XML message

<passenger>
    <name>John</name>
    <age>28</age>
</passenger>

Based on the age value i want to determine whether a passenger is infant, child or adult, and direct message to a corresponding channel, i.e. infantChannel, childChannel or adultChannel. I want to use XPath to define conditions of the content based filter, since it is XML message.

Apache Camel Solution
With Apache Camel it is rather straight forward

<route>
    <from uri="file:src/test/resources/message?noop=true"/>
    <choice>
        <when>
            <xpath>/passenger/age &lt;= '1'</xpath>
            <log message="INFANT"/>
        </when>
        <when>
            <xpath>/passenger/age &gt; '1' and /passenger/age &lt;= '12'</xpath>
            <log message="CHILD"/>
        </when>
        <when>
            <xpath>/passenger/age &gt; '12'</xpath>
            <log message="ADULT"/>
        </when>
        <otherwise>
            <log message="ERROR"/>
        </otherwise>
    </choice>
</route>

Spring Integration Solution
Well... I wasn't able to figure out and run out of patience. That is why I am writing to this forum.

It was logical to use <xpath-router>, but based on the documentation the output channels are determined dynamically based on the result of the XPath expression.

What I am trying to do is the following

<si-xml:xpath-router id="passengerRouter" input-channel="passengerChannel" resolution-required="true" >
    <si-xml:xpath-expression expression="/passenger/age"/>
</si-xml:xpath-router>

Based on the doc, the XPath expressions are evaluated as NODESET and converter to list of strings, where every value of this list represents a channel name to which this message will be sent. In my case this will be just a list of integers from <age> message element and this this is not what I want. I just have four channels I want the message to be sent to.

So, my question is how to configure <xpath-router> to implement my case?

Thanks in advance.