Question

当自动装配存在于不同包中的字段时，我无法自动装配。

我的代码看起来像这样

注入课程

package com.vmware.vchs.networkservice.extensions.http
@Component
public class HttpServiceClient implements ContextAware
{
@Autowired
JMXAgent jMXAgent;
....
};

注入课程

package com.vmware.vchs.networkservice.monitoring;

@Component
public class JMXAgent {
};

我的组件扫描xml文件如下所示

<?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:bean="http://www.springframework.org/schema/context"
   xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/context
    http://www.springframework.org/schema/context/spring-context-3.0.xsd"

<context:property-placeholder 
    location="classpath:environment.properties" 
    ignore-unresolvable="false"/>

<bean:component-scan base-package="com.vmware.vchs.networkservice"/>
</beans>

错误是

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Err
or creating bean with name 'httpServiceClient': Injection of autowired dependencies fai
led; nested exception is org.springframework.beans.factory.BeanCreationException: Could
not autowire field: com.vmware.vchs.networkservice.monitoring.JMXAgent com.vmware.vchs.
networkservice.extensions.http.HttpServiceClient.jmxAgent; nested exception is org.spri
ngframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [co
m.vmware.vchs.networkservice.monitoring.JMXAgent] found for dependency: expected at lea
st 1 bean which qualifies as autowire candidate for this dependency. Dependency annotat
ions: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

Answer 1

为了Automatically detecting classes and registering bean definitions我通常使用context而不是bean：

<?xml version="1.0" encoding="UTF-8"?>
<beans
    xmlns="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans 
            http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context 
            http://www.springframework.org/schema/context/spring-context.xsd">

  <context:component-scan base-package="org.example"/>

</beans>

<强>更新

<context:component-scan base-package="com.vmware.vchs.networkservice"/>
<context:component-scan base-package="com.vmware.vchs.networkservice.extensions.http"/>

Answer 2

我的程序正在从不同的xml读取。这就是找不到bean的原因

当两个不同的包在spring中相互链接时，依赖注入失败

2 个答案: