大家好，我是烤鸭：

    今天给大家分享简单的单点登录的实现方式。

    环境及jar包:

    springboot     1.5.10   

    redis    2.9.0    （可以用tomcat的session，但是无法解决多个tomcat共享session的问题）

    shiro    1.4.0    

    lombok    1.16.10    （可选,编译的时候自动生成get,set,toString()方法）

登录方法：

    主要是用户完成登录，登录信息写在cookie，

    服务器端存缓存(redis)中。

LoginService:

package xxx.xxx.system.service.impl;import java.io.Serializable;
import java.util.HashMap;
import java.util.List;
import java.util.Map;import org.apache.shiro.SecurityUtils;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.UsernamePasswordToken;
import org.apache.shiro.subject.Subject;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;import com.alibaba.fastjson.JSONObject;
import xxx.xxx.common.constant.IMsgEnum;
import xxx.xxx.common.resp.BaseMsgResp;
import xxx.xxx.common.utils.MD5Utils;
import xxx.xxx.entity.sys.UserDO;
import xxx.xxx.redis.cache.RedisManager;
import xxx.xxx.system.service.LoginService;
import xxx.xxx.system.service.UserService;@Service
public class LoginServiceImpl implements LoginService {@Autowiredprivate UserService userService;@Overridepublic BaseMsgResp login(String username, String password) throws AuthenticationException{BaseMsgResp resp = new BaseMsgResp();password = MD5Utils.encrypt(username, password);UsernamePasswordToken token = new UsernamePasswordToken(username, password);Subject subject = SecurityUtils.getSubject();subject.login(token);//获取用户Map<String, Object> params = new HashMap<>();params.put("username", username);List<UserDO> list = userService.list(params);if(list.size() > 1) {resp = new BaseMsgResp(IMsgEnum.SYSTEM_ANOMALY.getMsgCode()+"",IMsgEnum.SYSTEM_ANOMALY.getMsgText());return resp;}//tokenSerializable id = subject.getSession().getId();//将token放入redisRedisManager manager = RedisManager.getRedisSingleton();manager.set("sys:login:user_token_"+id.toString(),list.get(0).getUserId()+"",60*30);//防止同一个账号同时登录manager.set("sys:user:id_"+list.get(0).getUserId(), id.toString(),60*30);//用户信息manager.set("sys:login:user_info_"+list.get(0).getUserId(), JSONObject.toJSONString(list.get(0)),60*30);return resp;}
}

RedisManager.java

    用于redis初始化，和一些基本方法：

packagexxx.xxx.redis.cache;import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;/*** @author * @version V1.0*/import java.util.Set;
import java.util.concurrent.TimeUnit;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Configuration;import com.alibaba.fastjson.JSONObject;
import xxx.xxx.redis.config.RedisConstant;import lombok.Data;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;/****/
@Configuration
@ConfigurationProperties(value="jedis.pool")
@Data
public class RedisManager {private final Logger logger = LoggerFactory.getLogger(this.getClass());volatile static RedisManager redisSingleton;private String host;private int port;private int expire;private int timeout;private String password = "";private static JedisPool jedisPool = null;//第几个仓库private String database;public String getDatabase() {if(null == database || "".equals(database)) return "0";return database;}public void setDatabase(String database) {this.database = database;}public RedisManager() {}public static RedisManager getRedisSingleton() {if(redisSingleton == null) {synchronized (RedisManager.class) {if(redisSingleton == null) return new RedisManager();}}return redisSingleton;}/*** 初始化方法*/public void init() {if (jedisPool == null) {if (password != null && !"".equals(password)) {jedisPool = new JedisPool(new JedisPoolConfig(), host, port, timeout, password);} else if (timeout != 0) {jedisPool = new JedisPool(new JedisPoolConfig(), host, port, timeout);} else {jedisPool = new JedisPool(new JedisPoolConfig(), host, port);}}}/*** 给Redis中Set集合中某个key值设值* * @param key* @param value*/public void set(String key, String value) {Jedis jedis = null;try {jedis = jedisPool.getResource();jedis.select(Integer.parseInt(getDatabase()));jedis.set(key, value);} catch (Exception e) {logger.error("Jedis set 异常" + e.getMessage());} finally {if (jedis != null) {jedis.close();}}}/*** 从Redis中Set集合中获取key对应value值* * @param key*/public String get(String key) {Jedis jedis = null;try {jedis = jedisPool.getResource();jedis.select(Integer.parseInt(getDatabase()));return jedis.get(key);} catch (Exception e) {logger.error("Jedis get 异常" + e.getMessage());return null;} finally {if (jedis != null) {jedis.close();}}}/*** 给Redis中Set集合中某个key值设值* * @param key* @param value*/public void set(String key, String value, long time) {Jedis jedis = null;try {jedis = jedisPool.getResource();jedis.select(Integer.parseInt(getDatabase()));jedis.set(key, value);jedis.set(key, value, "XX", "EX", time);} catch (Exception e) {logger.error("Jedis set 异常" + e.getMessage());} finally {if (jedis != null) {jedis.close();}}}/*** * @Title: expire * @Description: 设置指定key的生存时间   * @return Long    成功 返回 1 * @throws*/public Long expire(String key,int seconds) {Jedis jedis = null;try {jedis = jedisPool.getResource();jedis.select(Integer.parseInt(getDatabase()));return jedis.expire(key, seconds);} catch (Exception e) {logger.error("Jedis expire 异常" + e.getMessage());return null;} finally {if (jedis != null) {jedis.close();}}}/*** * @Title: exist * @Description: 判断key是否存在   * @return Boolean    返回类型 * @throws*/public Boolean exist(String key) {Jedis jedis = null;try {jedis = jedisPool.getResource();jedis.select(Integer.parseInt(getDatabase()));return jedis.exists(key);} catch (Exception e) {logger.error("Jedis exist 异常" + e.getMessage());return null;} finally {if (jedis != null) {jedis.close();}}}}

LoginInterceptor:

    每次请求都会经过拦截器，校验用户是否登录或者多个浏览器（客户端）登录。

    如果用户已登录，用这次请求cookie中的token和缓存中的比较，如果不一致，就把之前缓存中的用户信息清空。

    这样之前的用户如果再次操作，就会跳转到登陆页面。

package xxx.xxx.system.interceptor;import java.io.IOException;
import java.io.Serializable;
import java.lang.ProcessBuilder.Redirect;
import java.util.HashMap;
import java.util.Map;import javax.servlet.ServletOutputStream;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import org.apache.commons.lang3.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.shiro.SecurityUtils;
import org.apache.shiro.subject.Subject;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;import com.alibaba.fastjson.JSONObject;
import xxx.xxx.common.utils.LogUtils;
import xxx.xxx.redis.cache.RedisManager;
import xxx.xxx.system.utils.ShiroUtils;/*** ClassName: PlatformInterceptor date: 2015年12月30日 下午2:13:24 Description: 拦截器* * @author * @version* @since JDK 1.8*/
@Component
@EnableAutoConfiguration(exclude = ErrorMvcAutoConfiguration.class)
public class LoginInterceptor implements HandlerInterceptor {private static final Log logger = LogFactory.getLog(LoginInterceptor.class);@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {try {logger.info(LogUtils.getRequestLog(request));//校验用户是否已经登录,如果登录过,将之前用户踢掉,同时更新缓存中用户信息Subject subject = SecurityUtils.getSubject();Serializable token = subject.getSession().getId();RedisManager redisManager = RedisManager.getRedisSingleton();//获取用户idString userId = redisManager.get("sys:login:user_token_"+token.toString());if(StringUtils.isNotBlank(userId)) {String tokenPre = redisManager.get("sys:user:id_"+userId);if(!token.equals(tokenPre)) {//重定向到login.htmlredirect(request, response); return false;}else {Long expire = redisManager.ttl("sys:login:user_token_"+token.toString());//过期时间小于1分钟的,更新tokenif(expire < 1 * 60 * 1000) {redisManager.expire("sys:login:user_token_"+token.toString(), 60*30);}}}else {redirect(request, response); return false;}} catch (Exception e) {logger.info("preHandle="+e.getMessage());}return true;}@Overridepublic void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,ModelAndView modelAndView) throws Exception {}@Overridepublic void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)throws Exception {}//对于请求是ajax请求重定向问题的处理方法public void redirect(HttpServletRequest request, HttpServletResponse response) throws IOException{//获取当前请求的路径String basePath = request.getScheme() + "://" + request.getServerName() + ":"  + request.getServerPort()+request.getContextPath();
//        response.getOutputStream().write("账号在别处登录。".getBytes("UTF-8"));//如果request.getHeader("X-Requested-With") 返回的是"XMLHttpRequest"说明就是ajax请求，需要特殊处理 否则直接重定向就可以了if("XMLHttpRequest".equals(request.getHeader("X-Requested-With"))){//告诉ajax我是重定向response.setHeader("REDIRECT", "REDIRECT");//告诉ajax我重定向的路径response.setHeader("CONTENTPATH", basePath+"/login");response.setStatus(HttpServletResponse.SC_FORBIDDEN);}else{response.sendRedirect(basePath + "/login");}}
}

ShiroUtils.java

    shiro 工具类，获取subject对象。

package xxx.xxx.system.utils;import java.security.Principal;
import java.util.Collection;
import java.util.List;import org.apache.shiro.SecurityUtils;
import org.apache.shiro.session.Session;
import org.apache.shiro.session.mgt.eis.SessionDAO;
import org.apache.shiro.subject.Subject;
import org.springframework.beans.factory.annotation.Autowired;import xxx.xxx.entity.sys.UserDO;public class ShiroUtils {@Autowiredprivate static SessionDAO sessionDAO;public static Subject getSubjct() {return SecurityUtils.getSubject();}public static UserDO getUser() {Object object = getSubjct().getPrincipal();return (UserDO)object;}public static Integer getUserId() {return getUser().getUserId();}public static void logout() {getSubjct().logout();}public static List<Principal> getPrinciples() {List<Principal> principals = null;Collection<Session> sessions = sessionDAO.getActiveSessions();return principals;}
}

UserDO.java

    用户对象。

package xxx.xxx.entity.sys;import org.springframework.format.annotation.DateTimeFormat;import java.io.Serializable;
import java.util.Date;
import java.util.List;public class UserDO implements Serializable {private static final long serialVersionUID = 1L;//用户idprivate Integer userId;// 用户名private String username;// 用户真实姓名private String name;// 密码private String password;
}

application.yml

jedis :pool :host : 127.0.0.1port : 9001password: abcd123maxTotal: 100maxIdle: 10maxWaitMillis : 100000