How to implement basic authentication with acegi - no container dependency

I have always implemented basic authentication by depending on a specific container implementation - always with the drawback of not being able to easy switch between containers in development, test and production.
Now I stood in front of another implementation and decided to look into Acegi's possibilities. If Acegi could provide a basic authentication mechanism bundled in my application I could get rid of the container dependency.
I did use Acegi on one other project to do form based login, but at that time the API changed between each little minor release making it a pain to upgrade.
Now they promise to keep the API stable so I thought it was about time give it a new fair chance to improve the first impression I got.

And I must say it did!

Following is a simple securityContext.xml needed to perform basic authentication using spring and acegi.
I provided a very simple UserDetailsService for the sake of the example. You should probably be using the
org.acegisecurity.userdetails.jdbc.JdbcDaoImpl implementation instead - or any other implementation that suites your setup.

securityContext.xml (download)

<?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:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="
  http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
  http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">

<!-- ======================== FILTER CHAIN ======================= -->

<bean id="filterChainProxy"
class="org.acegisecurity.util.FilterChainProxy">
<property name="filterInvocationDefinitionSource">
<value>
 CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON
 PATTERN_TYPE_APACHE_ANT
 /**=httpSessionContextIntegrationFilter,basicProcessingFilter,exceptionTranslationFilter,filterInvocationInterceptor
</value>
</property>
</bean>

<!-- responsible for setting up a security context holder for other
authentication mechanisms to work with -->
<bean id="httpSessionContextIntegrationFilter"
class="org.acegisecurity.context.HttpSessionContextIntegrationFilter">
<!-- no session should ever be created. We are processing basic
  authentication credentials on each request -->
<property name="allowSessionCreation" value="false"/>
</bean>

<!-- Processes basic authentication headers and works together with the
provided authentication manager and
entry point to perform basic authentication -->
<bean id="basicProcessingFilter"
class="org.acegisecurity.ui.basicauth.BasicProcessingFilter">
<property name="authenticationManager" ref="authenticationManager"/>
<property name="authenticationEntryPoint"
ref="authenticationEntryPoint"/>
</bean>

<!-- filter responsible for access decisions. What urlrequests may be
processed by which roles -->
<bean id="filterInvocationInterceptor"
class="org.acegisecurity.intercept.web.FilterSecurityInterceptor">
<property name="authenticationManager" ref="authenticationManager"/>
<property name="accessDecisionManager">
<ref local="httpRequestAccessDecisionManager"/>
</property>
<property name="objectDefinitionSource">
<value>
 CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON
 PATTERN_TYPE_APACHE_ANT
 /**=USER
</value>
</property>
</bean>

<!-- filter responsible for translating exceptions and delegating to the
provided authenticationEntryPoint -->
<bean id="exceptionTranslationFilter"
class="org.acegisecurity.ui.ExceptionTranslationFilter">
<property name="authenticationEntryPoint"
ref="authenticationEntryPoint"/>
</bean>

<!-- ======================== AUTHENTICATION ======================= -->

<bean id="authenticationEntryPoint"
class="org.acegisecurity.ui.basicauth.BasicProcessingFilterEntryPoint">
<property name="realmName" value="Protected atlight"/>
</bean>

<bean id="authenticationManager"
class="org.acegisecurity.providers.ProviderManager">
<property name="providers">
<list>
 <ref local="daoAuthenticationProvider"/>
</list>
</property>
</bean>

<bean id="daoAuthenticationProvider"
class="org.acegisecurity.providers.dao.DaoAuthenticationProvider">
<property name="userDetailsService" ref="simpleUserDetailsService"/>
</bean>

<!-- a simple simple UserDetailsService -->
<bean id="simpleUserDetailsService"
class="com.blogspot.ancientprogramming.security.SimpleUserDetailsService" />

<bean id="httpRequestAccessDecisionManager"
class="org.acegisecurity.vote.AffirmativeBased">
<property name="allowIfAllAbstainDecisions" value="false"/>
<property name="decisionVoters">
<list>
 <ref local="roleVoter"/>
</list>
</property>
</bean>

<bean id="roleVoter" class="org.acegisecurity.vote.RoleVoter">
<property name="rolePrefix" value=""/>
</bean>
</beans>

web.xml
Together with this spring, acegi configuration in your web.xml you are up and running.

<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
<display-name>Archetype Created Web Application</display-name>

<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/securityContext.xml</param-value>
</context-param>

<filter>
<filter-name>Acegi Filter Chain Proxy</filter-name>
<filter-class>org.acegisecurity.util.FilterToBeanProxy</filter-class>
<init-param>
<param-name>targetClass</param-name>
<param-value>org.acegisecurity.util.FilterChainProxy</param-value>
</init-param>
</filter>

<filter-mapping>
<filter-name>Acegi Filter Chain Proxy</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>

<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
</web-app>

Sample (download)
I also provided a simple webapp demonstrating the implementation, just:

1. download
2. unzip
   
3. type $mvn jetty:run
4. go to: http://localhost:8080/basicAcegiExample
5. type user, password as credentials