java - 为什么将类注释为@Service 不创建 bean？

Question

我有这样的类(class):

@Service("userDetailsService") 
public class MyUserDetailsService implements UserDetailsService {
    ...

并努力做到:

<authentication-manager>
    <authentication-provider user-service-ref="userDetailsService">
    </authentication-provider>
</authentication-manager>

我遇到了以下错误:

Cannot resolve reference to bean 'userDetailsService' while setting bean property 'userDetailsService'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'userDetailsService' is defined

真的有必要声明bean吗？在这种情况下:

<beans:bean id="myUserDetailsService" class="my.package.services.MyUserDetailsService" />

编辑

这是我的 security.xml 文件:

<beans:beans xmlns="http://www.springframework.org/schema/security"
    xmlns:beans="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:jdbc="http://www.springframework.org/schema/jdbc" 
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
           http://www.springframework.org/schema/jdbc
           http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd
           http://www.springframework.org/schema/security
           http://www.springframework.org/schema/security/spring-security-3.0.xsd">

    <http>
        <form-login login-page="/login/"
            authentication-failure-url="/fail/" />
        <logout logout-success-url="/" />
    </http>

    <context:annotation-config />
    <context:component-scan base-package="my.package" />

    <authentication-manager>
        <authentication-provider user-service-ref="myUserDetailsService">
            <!-- <password-encoder hash="md5" /> -->
        </authentication-provider>
    </authentication-manager>

</beans:beans>

原因:

The matching wildcard is strict, but no declaration can be found for element 'context:annotation-config'.

Answer 1

您缺少上下文的架构位置。

所以你的 xml 应该开始于:

<beans:beans xmlns="http://www.springframework.org/schema/security"
    xmlns:beans="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:jdbc="http://www.springframework.org/schema/jdbc" 
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
           http://www.springframework.org/schema/jdbc
           http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd
           http://www.springframework.org/schema/security
           http://www.springframework.org/schema/security/spring-security-3.0.xsd
           http://www.springframework.org/schema/context 
           http://www.springframework.org/schema/context/spring-context-3.0.xsd">