初識Spring Security

       xmlns:security="http://www.springframework.org/schema/security"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/security
       http://www.springframework.org/schema/security/spring-security.xsd">

    <!--http元素用于定義Web相關(guān)權(quán)限控制。-->
    <!--intercept-url定義了一個權(quán)限控制的規(guī)則。
    pattern屬性表示我們將對哪些url進(jìn)行權(quán)限控制，其也可以是一個正則表達(dá)式，如上的寫法表示我們將對所有的URL進(jìn)行權(quán)限控制；
    access屬性表示在請求對應(yīng)的URL時需要什么權(quán)限，默認(rèn)配置時它應(yīng)該是一個以逗號分隔的角色列表，請求的用戶只需擁有其中的一個角色就能成功訪問對應(yīng)的URL。
    這里的“ROLE_USER”表示請求的用戶應(yīng)當(dāng)具有ROLE_USER角色。“ROLE_”前綴是一個提示Spring使用基于角色的檢查的標(biāo)記。-->
    <!--注：auto-config="true"時，SpringSecurity發(fā)現(xiàn)沒有登錄回自動創(chuàng)建登陸頁面-->
    <security:http auto-config="true">
        <security:intercept-url pattern="/**" access="ROLE_USER"/>
    </security:http>

    <!--使用AuthenticationManager 進(jìn)行認(rèn)證相關(guān)配置-->
    <!--authentication-manager元素指定了一個AuthenticationManager，其需要一個AuthenticationProvider（對應(yīng)authentication-provider元素）來進(jìn)行真正的認(rèn)證-->
    <security:authentication-manager>
        <security:authentication-provider>
            <security:user-service>
                <security:user name="user" password="user" authorities="ROLE_USER"/>
                <security:user name="admin" password="admin" authorities="ROLE_USER, ROLE_ADMIN"/>
            </security:user-service>
        </security:authentication-provider>
    </security:authentication-manager>
</beans>

 <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/applicationContext.xml,/WEB-INF/spring-security.xml</param-value>
    </context-param>

<filter>
        <filter-name>springSecurityFilterChain</filter-name>
        <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>springSecurityFilterChain</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
    <filter>
        <filter-name>springSecurityFilterChain</filter-name>
        <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>springSecurityFilterChain</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/applicationContext.xml,/WEB-INF/spring-security.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>*.do</url-pattern>
    </servlet-mapping>
</web-app>