我有两个配置类，如下面的
@Configuration
public class EnvConfiguration {
@Autowired
public RAMTaskDAO ramTaskDAO;
@Autowired
public MongoTaskDAO mongoTaskDAO;
@Bean
@Qualifier("ram")
public TaskDAO ramTaskDAO() {
return ramTaskDAO;
}
@Bean
@Qualifier("mongo")
public TaskDAO mongoTaskDAO() {
return mongoTaskDAO;
}
}
@Configuration
@Profile("dev")
public class DevEnvConfiguration extends EnvConfiguration {
@Bean
@Qualifier("taskDao")
public TaskDAO taskDAO() {
return ramTaskDAO;
}
}
我的主要课程如下所示：
@Component
public class TaskDAOUsageDemonstrator {
@Autowired
@Qualifier("taskDao")
public TaskDAO taskDao;
@Autowired
@Qualifier("ram")
public TaskDAO ramTaskDao;
@Autowired
@Qualifier("mongo")
public TaskDAO mongoTaskDao;
@ForSpring
private TaskDAOUsageDemonstrator() {
}
public static void main(String[] args) {
GenericXmlApplicationContext context = new GenericXmlApplicationContext();
context.getEnvironment().setActiveProfiles("dev");
context.load("applicationContext.xml");
context.refresh();
}
问题：
当Spring尝试实例化TaskDAOUsageDemonstrator时，它无法找到限定符的TaskDAO＆＃34; mongo＆＃34;由于某些原因。我可以通过其他两个限定符来获得Bean，但不仅仅是使用＆＃34; mongo＆＃34;。我试图将限定符名称重命名为mongo1，但事情并没有改变。
更新的 我试图在DevEnvConfiguration中返回mongoTaskDao而不是ramTaskDAO，用于限定符＆＃39; taskDao＆＃39;，我能够得到一个mongoTaskDao bean。出于某种原因，键入：TaskDAO with qualifier＆＃34; mongo＆＃34;只会导致问题。
异常追踪：
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'taskDAOUsageDemonstrator': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: public com.mb.taskmanager.TaskDAO com.mb.taskmanager.TaskDAOUsageDemonstrator.mongoTaskDao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.mb.taskmanager.TaskDAO] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true), @org.springframework.beans.factory.annotation.Qualifier(value=mongo)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:287)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1106)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:270)
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1113)
at com.mb.taskmanager.TaskDAOUsageDemonstrator.demoRamTaskDaoAutowired(TaskDAOUsageDemonstrator.java:84)
at com.mb.taskmanager.TaskDAOUsageDemonstrator.main(TaskDAOUsageDemonstrator.java:53)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: public com.mb.taskmanager.TaskDAO com.mb.taskmanager.TaskDAOUsageDemonstrator.mongoTaskDao; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.mb.taskmanager.TaskDAO] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true), @org.springframework.beans.factory.annotation.Qualifier(value=mongo)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:513)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:92)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:284)
... 11 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.mb.taskmanager.TaskDAO] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true), @org.springframework.beans.factory.annotation.Qualifier(value=mongo)}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:947)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:816)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:730)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:485)
... 13 more
更不用说RAMTaskDAO和MongoTaskDAO完全相同：
@Component
@Scope("singleton")
public class RAMTaskDAO implements TaskDAO {
private ConcurrentHashMap<String, BackendTask> taskMap;
public RAMTaskDAO() {
taskMap = new ConcurrentHashMap<String, BackendTask>();
}
...
}
@Component
@Scope("singleton")
public class MongoTaskDAO implements TaskDAO {
@Autowired
public MongoOperations mongoOperations;
public MongoTaskDAO() {
}
...
}
更新：
applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
xmlns:mongo="http://www.springframework.org/schema/data/mongo"
xmlns:rabbit="http://www.springframework.org/schema/rabbit"
xsi:schemaLocation="http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.1.xsd
http://www.springframework.org/schema/data/mongo
http://www.springframework.org/schema/data/mongo/spring-mongo-1.0.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
http://www.springframework.org/schema/rabbit
http://www.springframework.org/schema/rabbit/spring-rabbit.xsd">
<import resource="common-spring.xml" />
<import resource="mongo-spring.xml" />
<import resource="rabbit-spring.xml" />
<bean
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="location" value="test/app.properties" />
</bean>
<context:component-scan base-package="com.mb" />
<context:annotation-config />
</beans>
mongo-spring.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
xmlns:mongo="http://www.springframework.org/schema/data/mongo"
xsi:schemaLocation="http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/data/mongo
http://www.springframework.org/schema/data/mongo/spring-mongo-1.0.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">
<bean
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="location" value="prod/app.properties" />
</bean>
<context:component-scan base-package="com.mb.taskmanager.db" />
<context:annotation-config />
<mongo:mongo host="${mongo.host}" port="${mongo.port}" />
<mongo:db-factory dbname="${mongo.dbname}" mongo-ref="mongo"
username="${mongo.user}" password="${mongo.pwd}" />
<bean id="mongoTemplate" class="org.springframework.data.mongodb.core.MongoTemplate">
<constructor-arg name="mongoDbFactory" ref="mongoDbFactory" />
</bean>
</beans>
app.properties
mongo.host=myhost.com
mongo.port=27017
mongo.dbname=framework-unittesting-db
mongo.user=xxxxxxx
mongo.pwd=xxxxx
rabbit.host=localhost
rabbit.user=xxxx
rabbit.pwd=xxxxxxxxxx
TaskManager
TaskManager就像这样开始
public class TaskManager {
@Autowired
@Qualifier("taskDao")
protected TaskDAO taskDAO;
@Autowired
private TaskBrokerFactory taskBrokerFactory;
private TaskManager() {
}
....
}