从处理器内部设置骆驼交换属性

Question

这里是Java 8和Camel 2.19.x。我有以下骆驼路线：

<route id="widgetProcessing">
  <from uri="activemq:inputQueue"/>
  <to uri="{{widgetFetcher}}"/>
</route>

和WidgetFetcher处理器：

@Component("widgetFetcher")
public class WidgetFetcher {
  private WidgetDao widgetDao;

  public WidgetFetcher(WidgetDao widgetDao) {
    this.widgetDao = widgetDao;
  }

  public Widget getWidgetToProcess() {
    // get the next widget id from the database
    final Integer firstWidgetId = widgetDao.getFirstSubmittedWidgetId();

    // Do lots of stuff with 'firstWidgetId' down here...
  }
}

<route id="widgetProcessing">
  <from uri="activemq:inputQueue"/>

  <setProperty propertyName="fizzId">
    <constant>null</constant>
  </setProperty>

  <to uri="{{widgetFetcher}}"/>

  <log message="fizzId = ${property[fizzId]}" loggingLevel="ERROR"/>
</route>

public Widget getWidgetToProcess(@ExchangeProperty("fizzId") final String fizzId) {
  // get the next widget id from the database
  final Integer firstWidgetId = widgetDao.getFirstSubmittedWidgetId();

  if (someMethodReturnsTrue()) {
    // Does this actually get saved outside the 
    log.info("About to update fizzId...")
    fizzId = UUID.randomUUID().toString();
  }

  // Do lots of stuff with 'firstWidgetId' down here...
}

About to update fizzId...
fizzId = null

Answer 1

不是将属性传入处理器，而是接受交换--然后就可以在交换上设置属性。