Java サーブレットは分散セッション管理をどのように実装しますか?

<distributable>true</distributable>

<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
    <version>3.6.0</version>
</dependency>

import redis.clients.jedis.Jedis;

public class SessionDistributionServlet extends HttpServlet {
    private static Jedis jedis = new Jedis("localhost", 6379);

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        // 获取会话属性
        String username = jedis.hget("session:" + req.getSession().getId(), "username");
        
        // 设置响应
        resp.getWriter().write("用户名：" + username);
    }

<dependency>
    <groupId>org.springframework.session</groupId>
    <artifactId>spring-session</artifactId>
    <version>2.3.5.RELEASE</version>
</dependency>

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.session.Session;
import org.springframework.session.SessionRepository;

public class SpringSessionServlet extends HttpServlet {
    @Autowired
    private SessionRepository<RedisSession> sessionRepository;

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        // 获取会话属性
        String username = sessionRepository.findById(req.getSession().getId()).getAttribute("username");
        
        // 设置响应
        resp.getWriter().write("用户名：" + username);
    }