Camel Splitters 执行后是否保留交换体？答案

【问题标题】：Do Camel Splitters preserve exchange body after they execute?Camel Splitters 执行后是否保留交换体？
【发布时间】：2019-03-27 20:36:21
【问题描述】：

Java 8 和 Apache Camel 2.19.5 在这里。我有以下 bean 处理器：

@Component("foobarResolver")
public class FoobarResolver {
  public List<Foobar> resolve(Fizzbuzz fizzbuzz) {
    List<Foobar> foobars = new ArrayList<Foobar>();

    // Use some logic in here to make the fizzbuzz populate the foobars list.

    return foobars;
  }
}

@Component("fizzbuzzProcessor")
public class FizzbuzzProcessor {
  public FizzbuzzOutput process(Fizzbuzz fizzbuzz) {
    // Blah whatever
  }
}

还有以下骆驼路线：

<route id="fizzbuzzHandler">
  <!-- XML '<fizzbuzz>' messages get sent here by an upstream process -->
  <from uri="activemq:fizzbuzzes"/>

  <!-- Use XStream to deserialize the XML into a 'Fizzbuzz' POJO instance -->
  <unmarshal ref="xs"/>

  <split>
    <method ref="bean:foobarResolver"/>
    <to uri="activemq:analyze"/>
  </split>

  <!-- Now assuming our body is once again the Fizzbuzz we can just continue as normal... -->

  <!-- Process the fizzbuzz -->
  <to uri="bean:fizzbuzzProcessor"/>

  <!-- Send fizzbuzzProcessor's output to 'output' queue -->
  <to uri="activemq:output"/>
</route>

如您所见，反序列化的Fizzbuzz 实例被发送到FoobarResolver bean 处理器，该处理器将该实例转换为List<Foobar>，然后将每个Foobar 发送到analyze 队列，一个一个。至少这就是我的设计意图！

我很好奇的是：分裂之后，交换体变成了什么？它是“还原”回Fizzbuzz（这是我想要的），还是现在是FoobarResolver 产生的List<Foobar>（这不是我想要的）？如果正文现在是List<Foobar>，我该如何重新配置，让FizzbuzzProcessor 接收Fizzbuzz？

【问题讨论】：

标签： java apache-camel integration-patterns

【解决方案1】：

它似乎恢复到分裂前的身体：

@SpringBootApplication
public class SocamelApplication extends RouteBuilder implements ApplicationRunner {
    @Autowired
    private FooProcessor fooProcessor;

    public static void main(String[] args) {
        SpringApplication.run(SocamelApplication.class, args);
    }

    @Override
    public void run(ApplicationArguments args) throws Exception {
        Thread.sleep(5000);
    }

    @Override
    public void configure() throws Exception {
        from("timer://foo?period=100&repeatCount=1").setBody()
                                                    .constant(Arrays.asList("Hello", "World"))
                                                    .log("1 >>> ${body} ")
                                                    .split(body())
                                                    .log("2 >>> ${body}")
                                                    .bean(fooProcessor)
                                                    .log("3 >>> ${body}")
                                                    .end()
                                                    .log("4 >>> ${body}");

    }

    @Bean
    public FooProcessor fooProcessor() {
        return new FooProcessor();
    }

}

class FooProcessor implements Processor {

    @Override
    public void process(Exchange exchange) throws Exception {
        String reverseMe = exchange.getIn()
                                   .getBody(String.class);

        String reversed = new StringBuilder(reverseMe).reverse()
                                                      .toString();

        exchange.getOut()
                .setBody(reversed);
    }

}

产量：

1 >>> Hello,World 
2 >>> Hello
3 >>> olleH
2 >>> World
3 >>> dlroW
4 >>> Hello,World

【讨论】：