因为我必须使用遗留应用程序,所以我想使用来自单独 Spring 上下文的 bean。
我使用这样的 XML bean 定义创建了这个单独的 Spring 上下文:
<?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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
https://www.springframework.org/schema/context/spring-context.xsd">
<context:component-scan base-package="some.different.package"/>
<bean id="connectionUrlFactory" class="my.ConnectionUrlFactory">
<property name="dbServer" value="server.url.com"/>
<property name="dbDatabasename" value="database"/>
<property name="dbClientName" value="client"/>
</bean>
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="com.sybase.jdbc4.jdbc.SybDriver"/>
<property name="url" ref="connectionUrlFactory"/>
<property name="username" value="user"/>
<property name="password" value="password"/>
</bean>
</beans>
在我自己的“外部”Spring Boot 应用程序中,我有这样的上下文@Configuration
:
@Configuration
class Configuration {
private final ApplicationContext applicationContext;
Configuration() {
applicationContext = new ClassPathXmlApplicationContext("beans.xml");
}
@Bean
DaoSybaseImpl sybaseDao() {
return applicationContext.getBean(DaoSybaseImpl.class);
}
@Bean
DataSource sybaseDataSource() {
return applicationContext.getBean(DataSource.class);
}
}
但是,当我运行应用程序时,我收到此错误:
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'sybaseDao': Unsatisfied dependency expressed through method 'setDataSource' parameter 0; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'javax.sql.DataSource' available: expected single matching bean but found 2: postgresDataSource,sybaseDataSource
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.resolveMethodArguments(AutowiredAnnotationBeanPostProcessor.java:768)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:720)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:119)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:399)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1413)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:601)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:524)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1380)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1300)
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:887)
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791)
... 125 more
Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'javax.sql.DataSource' available: expected single matching bean but found 2: postgresDataSource,sybaseDataSource
at org.springframework.beans.factory.config.DependencyDescriptor.resolveNotUnique(DependencyDescriptor.java:220)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1358)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1300)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.resolveMethodArguments(AutowiredAnnotationBeanPostProcessor.java:760)
... 140 more
当我sybaseDataSource
从我@Configuration
的 中删除时,错误消失了(我的应用程序由于丢失而无法启动sybaseDataSource
)。
似乎遗产ClassPathXmlApplicationContext
确实知道我的“外部” Spring Boot 上下文。怎么会这样?