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Only at first when does the expression work in apache camel pick?

I have this route that checks if the body starts with "01" or "02" and calls it beans. the problem is that only the first one works. for example if I post a message that starts with "01" it works fine, but if my message starts with "02" the other part gets executed and I get an error with an empty body.

<route id="genericService">
        <from uri="servlet:///genericService"/>
        <choice>
            <when>
                <simple>${body} regex "^01.*$"</simple>
                <bean ref="cardFacade" method="getBalance" />
            </when>
            <when>
                <simple>${body} regex "^02.*$"</simple>
                <bean ref="depositFacade" method="getBalance" />
            </when>
            <otherwise>
                <transform>
                    <simple>error:  ${body}</simple>
                </transform>
            </otherwise>
        </choice>
        <marshal>
            <json />
        </marshal>
        <transform>
            <simple>${body}</simple>
        </transform>
    </route>
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The problem is that the servlet component provides the body as a stream that can only be read once. Thus, you either need to enable stream caching or convert the message body to a non stream type such as String or byte [].

You can find more information here



Also see 1st box on this page

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I had the same problem in Java DSL (not compilation problem). What I need to do is add .endchoice () for each selection like below:



from(endPointTopic)
.errorHandler(deadLetterChannel)
.log("Message from Topic is ${body} & header string is ${header.Action}" )          
.choice()
    .when(header("Action").isEqualTo("POST"))
        .setHeader(Exchange.HTTP_METHOD, constant("POST"))
        .setHeader("Content-Type", constant("application/json"))
        .convertBodyTo(String.class)
        .to("log:like-to-see-all?level=INFO&showAll=true&multiline=true")
        .to(privateApi)
        .log("POST request for " + topicName)
        .endChoice()
    .when(header("Action").isEqualTo("PUT"))
        .setHeader(Exchange.HTTP_METHOD, constant("PUT"))
        .setHeader("Content-Type", constant("application/json"))
        .convertBodyTo(String.class)
        .to("log:like-to-see-all?level=INFO&showAll=true&multiline=true")
        .to(privateApi)
        .log("PUT request for " + topicName)
        .endChoice()
    .when(header("Action").isEqualTo("DELETE"))
        .setHeader(Exchange.HTTP_METHOD, constant("DELETE"))
        .setHeader("Content-Type", constant("application/json"))
        .convertBodyTo(String.class)
        .to("log:like-to-see-all?level=INFO&showAll=true&multiline=true")
        .to(privateApi)
        .log("DELET request for " + topicName)
        .endChoice()
    .otherwise()
        .setHeader(Exchange.HTTP_METHOD, constant("GET"))
        .setHeader("Content-Type", constant("application/json"))
        .convertBodyTo(String.class)
        .to("log:like-to-see-all?level=INFO&showAll=true&multiline=true")
        .to(privateApi)
        .log("Un-known HTTP action so posting to GET queue")
        .endChoice();
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