Spring integration Spring集成中的异常-在声明通道bean时定义了多个通道

我是spring集成的新手，我使用以下代码

package services.api;

public interface GreetingService {
    public void greetUsers(String userName);

}


package services.impl;

import services.api.GreetingService;

public class GreetServiceImpl implements GreetingService {

    @Override
    public void greetUsers(String userName) {
        if (userName != null && userName.trim().length() > 0) {
            System.out.println("Hello " + userName);
        }

    }

}


package main;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.integration.Message;
import org.springframework.integration.MessageChannel;
import org.springframework.integration.support.MessageBuilder;

public class Main {

    public static void main(String[] args) 
    {
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");



        MessageChannel messageChannel = applicationContext.getBean(MessageChannel.class);
        Message<String> message = MessageBuilder.withPayload("World").build();
        messageChannel.send(message);
    }

}


<?xml version="1.0" encoding="UTF-8"?>

<beans:beans xmlns:beans="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://springframework.org/schema/integration"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
    http://springframework.org/schema/integration http://springframework.org/schema/integration/spring-integration.xsd">


    <channel id="pushChannel" />

    <service-activator input-channel="pushChannel" ref="service"
        method="greetUsers" />


    <beans:bean id="service" class="services.impl.GreetServiceImpl" />



</beans:beans>

---

我建议您阅读更多文档：

如您所见，框架提供了两个显式通道：

nullChannel

，

errorChannel

。 而且它们不是最后一个由框架填充的bean

要解决问题，只需将频道的

id

提供给

applicationContext.getBean

Mar 04, 2014 4:46:23 PM org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@34d0cdd0: startup date [Tue Mar 04 16:46:23 IST 2014]; root of context hierarchy
Mar 04, 2014 4:46:23 PM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
INFO: Loading XML bean definitions from class path resource [applicationContext.xml]
Mar 04, 2014 4:46:23 PM org.springframework.beans.factory.config.PropertiesFactoryBean loadProperties
INFO: Loading properties file from URL [jar:file:/D:/Personal%20Data/Softwares/spring-framework-4.0.0.RELEASE-dist/SpringIntegration/spring-integration-3.0.0.RELEASE-dist/spring-integration-3.0.0.RELEASE/libs/spring-integration-core-3.0.0.RELEASE.jar!/META-INF/spring.integration.default.properties]
Mar 04, 2014 4:46:23 PM org.springframework.integration.config.xml.IntegrationNamespaceHandler registerHeaderChannelRegistry
INFO: No bean named 'integrationHeaderChannelRegistry' has been explicitly defined. Therefore, a default DefaultHeaderChannelRegistry will be created.
Mar 04, 2014 4:46:23 PM org.springframework.integration.config.xml.DefaultConfiguringBeanFactoryPostProcessor registerErrorChannel
INFO: No bean named 'errorChannel' has been explicitly defined. Therefore, a default PublishSubscribeChannel will be created.
Mar 04, 2014 4:46:23 PM org.springframework.integration.config.xml.DefaultConfiguringBeanFactoryPostProcessor registerTaskScheduler
INFO: No bean named 'taskScheduler' has been explicitly defined. Therefore, a default ThreadPoolTaskScheduler will be created.
Mar 04, 2014 4:46:23 PM org.springframework.beans.factory.config.PropertiesFactoryBean loadProperties
INFO: Loading properties file from URL [jar:file:/D:/Personal%20Data/Softwares/spring-framework-4.0.0.RELEASE-dist/SpringIntegration/spring-integration-3.0.0.RELEASE-dist/spring-integration-3.0.0.RELEASE/libs/spring-integration-core-3.0.0.RELEASE.jar!/META-INF/spring.integration.default.properties]
Mar 04, 2014 4:46:23 PM org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler initialize
INFO: Initializing ExecutorService  'taskScheduler'
Mar 04, 2014 4:46:23 PM org.springframework.context.support.DefaultLifecycleProcessor start
INFO: Starting beans in phase -2147483648
Mar 04, 2014 4:46:23 PM org.springframework.integration.endpoint.EventDrivenConsumer logComponentSubscriptionEvent
INFO: Adding {logging-channel-adapter:_org.springframework.integration.errorLogger} as a subscriber to the 'errorChannel' channel
Mar 04, 2014 4:46:23 PM org.springframework.integration.channel.PublishSubscribeChannel adjustCounterIfNecessary
INFO: Channel 'org.springframework.context.support.ClassPathXmlApplicationContext@34d0cdd0.errorChannel' has 1 subscriber(s).
Mar 04, 2014 4:46:23 PM org.springframework.integration.endpoint.EventDrivenConsumer start
INFO: started _org.springframework.integration.errorLogger
Mar 04, 2014 4:46:23 PM org.springframework.context.support.DefaultLifecycleProcessor start
INFO: Starting beans in phase 0
Mar 04, 2014 4:46:23 PM org.springframework.integration.endpoint.EventDrivenConsumer logComponentSubscriptionEvent
INFO: Adding {service-activator} as a subscriber to the 'pushChannel' channel
Mar 04, 2014 4:46:23 PM org.springframework.integration.channel.DirectChannel adjustCounterIfNecessary
INFO: Channel 'org.springframework.context.support.ClassPathXmlApplicationContext@34d0cdd0.pushChannel' has 1 subscriber(s).
Mar 04, 2014 4:46:23 PM org.springframework.integration.endpoint.EventDrivenConsumer start
INFO: started org.springframework.integration.config.ConsumerEndpointFactoryBean#0
Exception in thread "main" org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [org.springframework.integration.MessageChannel] is defined: expected single matching bean but found 3: pushChannel,nullChannel,errorChannel
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:312)
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:985)
    at main.Main.main(Main.java:17)