SpringSecurity使用步骤

一、导入jar包（使用maven构建项目导入其坐标）

<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-core</artifactId>
     <version>${spring.security.version}</version>
</dependency>
<dependency>
     <groupId>org.springframework.security</groupId>
     <artifactId>spring-security-taglibs</artifactId>
     <version>${spring.security.version}</version>
</dependency>

二、配置web.xml文件

<!-- 配置加载类路径的配置文件 -->
<context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath*:applicationContext.xml,classpath:spring-security.xml</param-value>
</context-param>

配置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>

三、创建spring-security.xml

<?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">

    <!-- 配置不拦截的资源 -->
    <security:http pattern="/login.jsp" security="none"/>
    <security:http pattern="/failer.jsp" security="none"/>
    <security:http pattern="/css/**" security="none"/>
    <security:http pattern="/img/**" security="none"/>
    <security:http pattern="/plugins/**" security="none"/>

    <!--
        配置具体的规则
        auto-config="true"    不用自己编写登录的页面，框架提供默认登录页面
        use-expressions="false"    是否使用SPEL表达式（没学习过）
    -->
    <security:http auto-config="true" use-expressions="false">
        <!-- 配置具体的拦截的规则 pattern="请求路径的规则" access="访问系统的人，必须有ROLE_USER的角色" -->
        <security:intercept-url pattern="/**" access="ROLE_USER,ROLE_ADMIN"/>

        <!-- 定义跳转的具体的页面 -->
        <security:form-login
                login-page="/login.jsp"
                login-processing-url="/login.do"
                default-target-url="/index.jsp"
                authentication-failure-url="/failer.jsp"
                authentication-success-forward-url="/pages/main.jsp"
        />

        <!-- 关闭跨域请求 -->
        <security:csrf disabled="true"/>

        <!-- 退出 -->
        <security:logout invalidate-session="true" logout-url="/logout.do" logout-success-url="/login.jsp"/>

    </security:http>

    <!-- 切换成数据库中的用户名和密码 -->
    <security:authentication-manager>
        <security:authentication-provider user-service-ref="userService">
            <!-- 配置加密的方式 -->
            <!--<security:password-encoder ref="passwordEncoder"/>-->
        </security:authentication-provider>
    </security:authentication-manager>

    <!--&lt;!&ndash; 配置加密类 &ndash;&gt;-->
    <bean id="passwordEncoder" class="org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder"/>

    <!-- 提供了入门的方式，在内存中存入用户名和密码
    <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>

此时该配置文件就相当于控制器。

四、创建service实现类，返回UserDetails对象

说明：在service实体类中调用dao方法，根据用户名查询数据库并返回查询结果，service将结果返回给springsecurity进行处理，根据用户名密码是否正确，身份是否符合，用户是否活跃最终判断用户的登陆成功与否。

package sun.ssm.service.Impl;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import sun.ssm.dao.UserDao;
import sun.ssm.domain.Role;
import sun.ssm.domain.UserInfo;
import sun.ssm.service.UserService;

import java.util.ArrayList;
import java.util.List;

/**
 * @Classname UserServiceImpl
 * @Description TODO
 * @Date 2020/10/30 13:38
 * @Created by Administrator
 */
@Service("userService")
@Transactional
public class UserServiceImpl implements UserService {
    @Autowired
    private UserDao userDao;

    @Override
    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
        UserInfo userinfo = userDao.findByUsername(username);
        User user=new User(userinfo.getUsername(),"{noop}"+userinfo.getPassword(),userinfo.getStatus()==0?false:true,true,true,true,getAuthority(userinfo.getRoles()));
        return user;
    }

    public List<SimpleGrantedAuthority> getAuthority(List<Role> roles){
        List<SimpleGrantedAuthority> list=new ArrayList<>();
        for(Role role:roles){
            list.add(new SimpleGrantedAuthority("ROLE_"+role.getRoleName()));
        }
        return list;
    }
}