Question

我对Camel来说相当新鲜。

我一直试图让Camel根据需要只通过FTP获取一个文件。我无法让它发挥作用。这是我尝试过的。让我知道什么是最好的方法和我的代码有什么问题。

1-在读取文件后发送空消息，当收到空消息时，请停止路由。

 from("direct:myStart")
    .routeId("routeA")
    .pollEnrich("ftp:...disconnect=true&sendEmptyMessageWhenIdle=true")
    .choice()
       .when(body().isNull()).process(RouteStopper("routeA"))
       .otherwise().to("validator:file.xsd")
    .to("somewhere")
    .end();

我的RouteStopper

public class RouteStopper implements Processor {

private String routeId;
private Thread stopper;

public RouteStopper(String routeId) {
    this.routeId = routeId;
}
@Override
public void process(Exchange exchange) throws Exception {
    if (stopper == null) {
        stopper = new Thread() {
            @Override
            public void run() {
                try {
                    exchange.getContext().stopRoute(routeId);
                } catch (Exception e) {
                }
            }
        };
    }
    stopper.start();
}

第一次拨打producerTemplate.sendBody("direct:myStart", null);

时，它确实正常

但是我第二次打电话给producerTemplate.sendBody("direct:myStart", null);我得到了这个：

org.apache.camel.component.direct.DirectConsumerNotAvailableException: No consumers available on endpoint: Endpoint[direct://myStart]. Exchange[Message: [Body is null]]

我想我想做的不是完全停止我的道路......所以我尝试了另一种方式......

2-实施PollingConsumerPollStrategy

public class FtpPollStrategy implements PollingConsumerPollStrategy {

@Override
public boolean begin(Consumer consumer, Endpoint endpoint) {
    return true;
}

@Override
public void commit(Consumer consumer, Endpoint endpoint, int polledMessages) {
    try {
        consumer.stop();
    }
    catch (Exception e) {
        e.printStackTrace();
    }
}

@Override
public boolean rollback(Consumer consumer, Endpoint endpoint, int retryCounter, Exception cause) throws Exception {
    return false;
}

}

在我的路线中：

from("ftp:....disconnect=true&pollStrategy=#ftpPollStrategy")

我得到的是

java.lang.IllegalArgumentException: Could not find a suitable setter for property: pollStrategy as there isn't a setter method with same type: java.lang.String nor type conversion possible: No type converter available to convert from type: java.lang.String to the required type: org.apache.camel.spi.PollingConsumerPollStrategy with value #ftpPollStrategy

3 - 如果我没有停止任何事情（如下面评论中所示），当找不到文件时，路线似乎永远不会停止轮询我的FTP 。我只打了一次路线：

producerTemplate.sendBody("direct:myStart", null);

路线

 from("direct:myStart")
.routeId("routeA")
.pollEnrich("ftp:...disconnect=true&sendEmptyMessageWhenIdle=true")
.to("validator:file.xsd")
.to("somewhere")
.end();

查看日志：

2015-08-05 08:55:28,942 DEBUG [correlation-ids:faad163b-f68e-4e91-b5fd-e5e2f86d42bd,user:] [(camelContext)-1] (org.apache.camel.component.file.remote.RemoteFileConsumer:152) TelechargementMetadonneesRouteBuilder- Not connected/logged in, connecting to: ftp://pierre@localhost:21 2015-08-05 08:55:28,943 INFO [correlation-ids:faad163b-f68e-4e91-b5fd-e5e2f86d42bd,user:] [(camelContext)-1] (org.apache.camel.component.file.remote.RemoteFileConsumer:156) TelechargementMetadonneesRouteBuilder- Connected and logged in to: ftp://pierre@localhost:21 2015-08-05 08:55:28,945 DEBUG [correlation-ids:faad163b-f68e-4e91-b5fd-e5e2f86d42bd,user:] [(camelContext)-1] (org.apache.camel.component.file.GenericFileConsumer:130) TelechargementMetadonneesRouteBuilder- Took 0.002 seconds to poll: 2015-08-05 08:55:28,945 DEBUG [correlation-ids:faad163b-f68e-4e91-b5fd-e5e2f86d42bd,user:] [(camelContext)-1] (org.apache.camel.component.file.remote.RemoteFileConsumer:121) TelechargementMetadonneesRouteBuilder- Disconnecting from: ftp://pierre@localhost:21 2015-08-05 08:55:29,446 DEBUG [correlation-ids:faad163b-f68e-4e91-b5fd-e5e2f86d42bd,user:] [(camelContext)-1] (org.apache.camel.component.file.remote.RemoteFileConsumer:152) TelechargementMetadonneesRouteBuilder- Not connected/logged in, connecting to: ftp://pierre@localhost:21 2015-08-05 08:55:29,447 INFO [correlation-ids:faad163b-f68e-4e91-b5fd-e5e2f86d42bd,user:] [(camelContext)-1] (org.apache.camel.component.file.remote.RemoteFileConsumer:156) TelechargementMetadonneesRouteBuilder- Connected and logged in to: ftp://pierre@localhost:21 2015-08-05 08:55:29,449 DEBUG [correlation-ids:faad163b-f68e-4e91-b5fd-e5e2f86d42bd,user:] [(camelContext)-1] (org.apache.camel.component.file.GenericFileConsumer:130) TelechargementMetadonneesRouteBuilder- Took 0.002 seconds to poll: 2015-08-05 08:55:29,449 DEBUG [correlation-ids:faad163b-f68e-4e91-b5fd-e5e2f86d42bd,user:] [(camelContext)-1] (org.apache.camel.component.file.remote.RemoteFileConsumer:121) TelechargementMetadonneesRouteBuilder- Disconnecting from: ftp://pierre@localhost:21

任何帮助将不胜感激。

Answer 1

所以我找到的解决方案是使用方案＃1，但停止并重新启动路由。

exchange.getContext().stopRoute(routeId);
exchange.getContext().startRoute(routeId);

Answer 2

您可以使用CountDownLatch来停止此处指定的路线 - http://camel.apache.org/how-can-i-stop-a-route-from-a-route.html。它对我来说就像魅力一样......

如何让Camel FTP只按需获取一次

2 个答案: