java接口用户上下文的设计与实现

package com.summo.filter;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.summo.context.GlobalUserContext;
import com.summo.context.UserContext;
import lombok.extern.slf4j.Slf4j;
import org.slf4j.MDC;
import org.springframework.stereotype.Component;
@Slf4j
@Component
public class WebFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        Filter.super.init(filterConfig);
    }
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
        throws IOException, ServletException {
        try {
            //获取本次接口的唯一码
            String token = java.util.UUID.randomUUID().toString().replaceAll("-", "").toUpperCase();
            MDC.put("requestId", token);
            //获取请求头
            HttpServletRequest httpServletRequest = (HttpServletRequest)servletRequest;
            HttpServletResponse httpServletResponse = (HttpServletResponse)servletResponse;
            log.info("当前请求链接为:[{}]", httpServletRequest.getRequestURL());
            //设置用户上下文
            UserContext userContext = new UserContext();
            userContext.setUserId(1L);
            GlobalUserContext.setUserContext(userContext);
            //执行doFilter，这行一定要加，否则程序会中断掉
            filterChain.doFilter(httpServletRequest, httpServletResponse);
        } catch (Exception e) {
            log.error("do doFilter exception", e);
        } finally {
            GlobalUserContext.clear();
            MDC.remove("requestId");
        }
    }
    @Override
    public void destroy() {
        Filter.super.destroy();
    }
}

<dependency>
  <groupId>com.alibaba</groupId>
  <artifactId>transmittable-thread-local</artifactId>
  <version>2.11.1</version>
</dependency>

private static final TransmittableThreadLocal<UserContext> USER_HOLDER = new TransmittableThreadLocal<>();

package com.summo.context;
import com.alibaba.ttl.TransmittableThreadLocal;
public class GlobalUserContext {
    private static final TransmittableThreadLocal<UserContext> USER_HOLDER = new TransmittableThreadLocal<>();
    /**
     * 设置上下文用户信息
     *
     * @param user 用户信息
     */
    public static void setUserContext(UserContext user) {
        USER_HOLDER.set(user);
    }
    /**
     * 获取上下文用户信息
     */
    public static UserContext getUserContext() {
        return USER_HOLDER.get();
    }
    /**
     * 清除上下文用户信息
     */
    public static void clear() {
        USER_HOLDER.remove();
    }
}

package com.summo.context;
import lombok.Data;
@Data
public class UserContext {
    /**
     * 用户ID
     */
    private Long userId;
}