1  Spring Security简介

Spring Security是一个能够为基于Spring的企业应用系统提供声明式的安全访问控制解决方案的安全框架。它提供了一组可以在Spring应用上下文中配置的Bean，充分利用了Spring IoC，DI（控制反转Inversion of Control ,DI:Dependency Injection 依赖注入）和AOP（面向切面编程）功能

2 使用Spring Security总共分五步  分别为

详细步骤如下

　　a、创建liJun_springSecurity项目（war）　

　　b、导入SpringSecurity的坐标（pom.xml）

　　c、配置spring-security.xml

　　d、配置web.xml

　　e、测试

详细步骤如下:

　  a 、创建liJun_springSecurity项目（war）　

　　b、导入SpringSecurity的坐标（pom.xml）

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
​
  <groupId>com.itheima</groupId>
  <artifactId>itheima_springsecurity</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>
​
  <properties>
    <spring.version>5.0.2.RELEASE</spring.version>
    <spring.security.version>5.0.1.RELEASE</spring.security.version>
  </properties>
  <dependencies>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-core</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context-support</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-test</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework.security</groupId>
      <artifactId>spring-security-web</artifactId>
      <version>${spring.security.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework.security</groupId>
      <artifactId>spring-security-config</artifactId>
      <version>${spring.security.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework.security</groupId>
      <artifactId>spring-security-taglibs</artifactId>
      <version>${spring.security.version}</version>
    </dependency>
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.1.0</version>
      <scope>provided</scope>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <!-- java编译插件 -->
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.2</version>
        <configuration>
          <source>1.8</source>
          <target>1.8</target>
          <encoding>UTF-8</encoding>
        </configuration>
      </plugin>
      <plugin>
        <groupId>org.apache.tomcat.maven</groupId>
        <artifactId>tomcat7-maven-plugin</artifactId>
        <configuration>
          <!-- 指定端口 -->
          <port>8080</port>
          <!-- 请求路径 -->
          <path>/</path>
        </configuration>
      </plugin>
    </plugins>
  </build>
</project>

c、配置spring-security.xml

在类加载路径resources下创建spring-security.xml配置文件，配置认证和授权信息

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:security="http://www.springframework.org/schema/security"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       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">
​
    <!--
        配置拦截的规则
        auto-config="使用自带的页面"
        use-expressions="是否使用spel表达式"，如果使用表达式：hasRole('ROLE_USER')
    -->
    <security:http auto-config="true" use-expressions="false">
        <!-- 配置拦截的请求地址，任何请求地址都必须有ROLE_USER的权限 -->
        <security:intercept-url pattern="/**" access="ROLE_USER"/>
    </security:http>
    
    <!-- 配置认证信息 -->
    <security:authentication-manager>
        <security:authentication-provider>
            <security:user-service>
                <security:user name="admin" password="{noop}admin" authorities="ROLE_USER"/>
            </security:user-service>
        </security:authentication-provider>
    </security:authentication-manager>
​
</beans>

d、配置web.xml

<?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">
​
  <!--Spring监听器指定配置文件位置-->
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:spring-security.xml</param-value>
  </context-param>
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
​
  <!--配置委派代理过滤器： filter-name必须是：springSecurityFilterChain -->
  <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>
​
</web-app>

e、测试

访问index.jsp页面，如果当前用户没有登录认证的话，则跳转到SpringSecurity的内置登录页面