Using InMemoryDaoImpl in spring security

I am trying to implement custom filter , authentication provider to authenticate users directly from requests . However I am getting the following the exception .

org.springframework.beans.factory.BeanCreationException: 
Error creating bean with name 'signedRequestAuthenticationProvider' defined in   ServletContext resource [/WEB-INF/applicationContext.xml]: 
 Cannot resolve reference to bean      'org.springframework.security.core.userdetails.memory.InMemoryDaoImpl' 
  while setting bean 
property 'userDetailsService'; nested exception is 
org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'org.springframework.security.core.userdetails.memory.InMemoryDaoImpl' 
 is defined at  org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:328)

My application context is

   <bean id="signedRequestAuthenticationProvider" class="src.SignedUsernamePasswordAuthenticationProvider">
       <property name="userDetailsService" ref="org.springframework.security.core.userdetails.memory.InMemoryDaoImpl"/>
   </bean>

My security.xml reads

<http auto-config="true" use-expressions="tr开发者_运维问答ue">
    <intercept-url pattern="/login*" access="hasRole('ROLE_ANONYMOUS')"/>
            <intercept-url pattern="/*" access="hasRole('ROLE_USER') or hasRole('ROLE_ADMIN')"/>

            <form-login login-page="/login.jsp"/>
            <custom-filter ref="requestHeaderFilter" before="FORM_LOGIN_FILTER"/>
   </http>

   <authentication-manager alias="authenticationManager">
    <authentication-provider ref="signedRequestAuthenticationProvider"/>
            <authentication-provider>
        <user-service>
            <user authorities="ROLE_USER" name="guest" password="guest"/>
                            <user authorities="ROLE_ADMIN" name="vinoth" password="vinoth"/>
        </user-service>
    </authentication-provider>
</authentication-manager>

Am I missing something ?

org.springframework.security.core.userdetails.memory.InMemoryDaoImpl is not a bean identifier, therefore you can't use it in ref attribute. You need to introduce identifier explicitly with id:

<bean id="signedRequestAuthenticationProvider" class="src.SignedUsernamePasswordAuthenticationProvider">
    <property name="userDetailsService" ref="userService"/>
</bean>

<authentication-manager alias="authenticationManager">
    <authentication-provider ref="signedRequestAuthenticationProvider"/>
    <authentication-provider>
        <user-service id = "userService">
            <user authorities="ROLE_USER" name="guest" password="guest"/>
            <user authorities="ROLE_ADMIN" name="vinoth" password="vinoth"/>
        </user-service>
    </authentication-provider>
</authentication-manager>