Exchange.getIn().getBody() 在第二次调用时返回骆驼的空字符串

Exchange.getIn().getBody() returns empty string in camel on second call(Exchange.getIn().getBody() 在第二次调用时返回骆驼的空字符串)

问题描述

我有 2 个相同的电话:

I have 2 identical calls:

String msg1 = exchange.getIn().getBody(String.class);
String msg2 = exchange.getIn().getBody(String.class);

在 msg1 中，我得到了正确的期望值，但 msg2 是一个空字符串.我没有设置 Out 消息，因此交换 In 消息应该仍然完好无损.请解释为什么会这样.

In msg1 I get the correct expected value , but msg2 is an empty string. I'm not setting the Out message , so the exchange In message should be still intact. Please explain why this is happening.

骆驼路线:

<camelContext xmlns="http://camel.apache.org/schema/spring">
    <route id="route1">
        <from uri="timer://myTimer?period=2000" />
        <setBody>
            <simple>Hello World ${header.firedTime}</simple>
        </setBody>
        <process ref="messageProcessor" />
        <to uri="http://localhost:8090"/>
    </route>
    <route id="route2">
        <from uri="jetty://http://localhost:8090" />
        <process ref="messageProcessor" />
    </route>
</camelContext>

处理器仅包含上面的 2 条语句.route1 中的处理是正确的，但在 route2 中我得到了描述的行为:第一次调用 - 有效字符串，第二次调用 - 空字符串.所以我想可能和HttpMessage转换有关.

The processor contains only the 2 statements from above. The processing in route1 is correct , but in route2 I get the described behaviour : first call - valid string , second call - empty string. So I think maybe it has something to do with HttpMessage conversion.

推荐答案

来自 http://camel.apache.org/jetty.html

Jetty 是基于流的，这意味着它接收到的输入被提交以骆驼为溪流.这意味着您将只能阅读流的内容一次.

Jetty is stream based, which means the input it receives is submitted to Camel as a stream. That means you will only be able to read the content of the stream once.

在使用两次或更多次之前将输入转换为字符串

Just convert the input in a String before use it twice or more times

<route id="route2">
    <from uri="jetty://http://localhost:8090" />
    <convertBodyTo type="String" />
    <process ref="messageProcessor" />
</route>

这篇关于Exchange.getIn().getBody() 在第二次调用时返回骆驼的空字符串的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！