如何解决 org.apache.camel.FailedToCreateProducerException CaughtExceptionMessage: Failed to create Producer for endpoint？

问题描述

我将 Camel 组件和代码从 2.X.X 升级到 3.7.3

此外，在 Java 8 中工作之前，我在 Java 11 中重新编译了源代码。

路线示例：

from(direct:xyz)
  .to(URL_A)
  .transform()
  ...

问题出现是因为在 to 之后，我得到 null。

我从 camel-http4 移到 camel-http，检查了库的属性，但仍然无法找出问题所在？

我得到的错误：

CaughtExceptionType: org.apache.camel.FailedToCreateProducerException  CaughtExceptionMessage: Failed to create Producer for endpoint: direct:xyz1616073923650. Reason: java.lang.NullPointerException  StackTrace: org.apache.camel.FailedToCreateProducerException: Failed to create Producer for endpoint: direct:xyz1616073923650. Reason: java.lang.NullPointerException
    at org.apache.camel.support.cache.DefaultProducerCache.acquireProducer(DefaultProducerCache.java:154)
    at org.apache.camel.processor.RecipientListProcessor.createProcessorExchangePairs(RecipientListProcessor.java:219)
    at org.apache.camel.processor.MulticastProcessor.process(MulticastProcessor.java:276)
    at org.apache.camel.processor.RecipientList.sendToRecipientList(RecipientList.java:222)
    at org.apache.camel.processor.RecipientList.process(RecipientList.java:185)
    at org.apache.camel.processor.Pipeline$PipelineTask.run(Pipeline.java:90)
    at org.apache.camel.impl.engine.DefaultReactiveExecutor$Worker.schedule(DefaultReactiveExecutor.java:148)
    at org.apache.camel.impl.engine.DefaultReactiveExecutor.scheduleMain(DefaultReactiveExecutor.java:60)
    at org.apache.camel.processor.Pipeline.process(Pipeline.java:147)
    at org.apache.camel.impl.engine.CamelInternalProcessor.process(CamelInternalProcessor.java:312)
    at org.apache.camel.component.direct.DirectProducer.process(DirectProducer.java:84)
    at org.apache.camel.impl.engine.SharedCamelInternalProcessor.process(SharedCamelInternalProcessor.java:218)
    at org.apache.camel.impl.engine.SharedCamelInternalProcessor$1.process(SharedCamelInternalProcessor.java:112)
    at org.apache.camel.impl.engine.DefaultAsyncProcessorAwaitManager.process(DefaultAsyncProcessorAwaitManager.java:83)
    at org.apache.camel.impl.engine.SharedCamelInternalProcessor.process(SharedCamelInternalProcessor.java:109)
    at org.apache.camel.support.cache.DefaultProducerCache.send(DefaultProducerCache.java:189)
    at org.apache.camel.impl.engine.DefaultProducerTemplate.send(DefaultProducerTemplate.java:176)
    at org.apache.camel.impl.engine.DefaultProducerTemplate.send(DefaultProducerTemplate.java:172)
    at org.apache.camel.impl.engine.DefaultProducerTemplate.send(DefaultProducerTemplate.java:153)
    at org.apache.camel.impl.engine.DefaultProducerTemplate.sendBody(DefaultProducerTemplate.java:187)
    at org.apache.camel.impl.engine.DefaultProducerTemplate.sendBody(DefaultProducerTemplate.java:457)

评论：我什至找不到离开这里的进一步方法，所以欢迎提出任何建议。

更新：

经过进一步调试后，我了解到该错误在路线中更远。

from(direct:xyz)
  .to(URL_A)
  .transform()
  ...
  .recipientList(exchangeProperty("event"))

更新 2：

我在 Camel Jira 版块中发布了一个 question/bug。

更新 3：

我添加了一个我的测试类的例子，被测试的路由看起来像上面的那个。

启动路由、上下文的 Spring Boot 应用程序：

@SpringBootApplication
@PropertySource("classpath:application-test.properties")
class TestApp {

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

测试本身：

@RunWith(springrunner.class)
@TestPropertySource(locations = "application-test.properties")
@SpringBoottest(classes = TestApp.class,webEnvironment = DEFINED_PORT)
public class FunctionalTest {

    @Autowired
    private EventConsumeCreator eventConsumerCreator;

    private List<Endpoint> consumers;

    private static final MockComponent MOCK_COMPONENT = new MockComponent();
    
    @Before
    public void before() {
        // Setting wiremock and LogAsserts

        consumers = eventConsumerCreator.getConsumers();
      
        consumers.clear();
        consumers.add(new MockEndpoint("direct:xyz",MOCK_COMPONENT));

    }

    @Test
    public checkNumEvents() {
      // Make requests to endpoints
      // Verify logs
      // Check wiremock asserts

      assertthat(numEvents(consumers),is(1));
    }

}

用于创建消费者的实用类：

@Component
public class EventConsumerCreator {

    private List<Endpoint> consumers = new LinkedList<>();

    private CamelContext camelContext;

    @Autowired
    public EventConsumerCreator(CamelContext camelContext) {
        this.camelContext = camelContext;
    }

    public List<Endpoint> getConsumers() {
        return consumers;
    }

    public Endpoint createConsumer(String identifier) {
        Endpoint endpoint = createEndpoint(identifier);
        consumers.add(endpoint);
        return endpoint;
    }

    private Endpoint createEndpoint(String identifier) {
        DirectComponent component = camelContext.getComponent("direct",DirectComponent.class);
        try {
            return component.createEndpoint("direct://" + identifier);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}

解决方法

感谢@Claus Ibsen 在 Jira 中的回复，我解决了这个问题。

解决方案是：

1. 在@Autowired private CamelContext camelContext中添加FunctionalTest
2. 在 @Before 中迭代所有端点并执行

camelContext.addEndpoint(endpoint.getEndpointUri(),endpoint);
endpoint.start();

3. 在 @After 语句中，停止运行端点

endpoint.stop();
camelContext.removeEndpoint(endpoint);

评论：如果您遇到这种情况，请考虑是否可以依赖 Spring/Camel 自动配置。如果没有，请尝试手动重新创建 Camel-ish 步骤。