Spring Securityでベーシック認証をするには？

applicationContext.xmlに以下を書き込む。

<security:http auto-config='true'>

<security:intercept-url pattern="/somepath/*" access="ROLE_USER"/>

<security:intercept-url pattern="/somepath/**" access="ROLE_USER"/>

     <security:http-basic />

</security:http>

<security:authentication-manager>

   <security:authentication-provider>

        <security:user-service>

        <security:user name="someid" password="somepass" authorities="ROLE_USER" />

        </security:user-service>

    </security:authentication-provider>

</security:authentication-manager>

http://syntx.io/adding-http-basic-auth-to-restful-services-in-java-and-spring/