public abstract class HandlerInterceptorAdapter implements AsyncHandlerInterceptor {

	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {
    // 在業(yè)務(wù)接口方法處理之前被調(diào)用，可以在這里對通用的header信息進行提取
		return true;
	}

	@Override
	public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
			@Nullable ModelAndView modelAndView) throws Exception {
		// 這個方法在業(yè)務(wù)接口方法執(zhí)行完成后，生成SpringMVC ModelAndView之前被調(diào)用
		// 今天這個案例我們不用此方法，故可以不實現(xiàn)。
	}
	
	@Override
	public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler,
			@Nullable Exception ex) throws Exception {
		// 這個方法在DispatcherServlet完全處理完成后被調(diào)用，可以在這里對ThreadLocal的內(nèi)容進行釋放
	}

	@Override
	public void afterConcurrentHandlingStarted(HttpServletRequest request, HttpServletResponse response,
			Object handler) throws Exception {
		// 這個方法用來處理異步主動，但也會先行調(diào)用preHandle，然后執(zhí)行此方法，異步線程完成后會執(zhí)行postHandle和afterCompletion兩方法，這里暫時用不上。
	}
}

public class ThreadLocal<T> {
  
  protected T initialValue() {
    return null;
  }

  public T get() {
		// 獲取當(dāng)前的線程
    Thread t = Thread.currentThread();
    ThreadLocalMap map = getMap(t);
    if (map != null) {
      ThreadLocalMap.Entry e = map.getEntry(this);
      if (e != null) {
        @SuppressWarnings("unchecked")
        T result = (T)e.value;
        return result;
      }
    }
    return setInitialValue();
  }

  private T setInitialValue() {
    T value = initialValue();
    Thread t = Thread.currentThread();
    ThreadLocalMap map = getMap(t);
    if (map != null)
      map.set(this, value);
    else
      createMap(t, value);
    return value;
  }

  public void set(T value) {
		// 獲取當(dāng)前的線程
    Thread t = Thread.currentThread();
    ThreadLocalMap map = getMap(t);
    if (map != null)
      map.set(this, value);
    else
      createMap(t, value);
  }

   public void remove() {
     ThreadLocalMap m = getMap(Thread.currentThread());
     if (m != null)
       m.remove(this);
   }

  ThreadLocalMap getMap(Thread t) {
    return t.threadLocals;
  }

  void createMap(Thread t, T firstValue) {
    t.threadLocals = new ThreadLocalMap(this, firstValue);
  }
}

@Data
public class CommonHeader implements Serializable {

	private static final long serialVersionUID = -3949488282201167943L;
	
	/**
	 * 真實ip
 	 */
	private String ip;

	/**
	 * 設(shè)備id
 	 */
	private String deviceId;

	/**
	 * 用戶uid
 	 */
	private Long uid;
	
	// 省略getter/setter/構(gòu)造器
}

/**
 * 將公共請求頭信息放在ThreadLocal中去
 */
public class RequestWrap {

	private static ThreadLocal<CommonHeader> current = new ThreadLocal<>();

  /**
	 * 獲取靜態(tài)的ThreadLocal對象
	 * @return
	 */
	public static ThreadLocal<CommonHeader> getCurrent() {
		return current;
	}
	
	/**
	 * 獲取ip
	 * @return
	 */
	public static String getIp() {
		CommonHeader request = current.get();
		if (request == null) {
			return StringUtils.EMPTY;
		}
		return request.getIp();
	}

	/**
	 * 獲取uid
	 * @return
	 */
	public static Long getUid() {
		CommonHeader request = current.get();
		if (request == null) {
			return null;
		}
		return request.getUid();
	}

	/**
	 * 獲取封裝對象
	 * @return
	 */
	public static CommonHeader getCommonReq() {
		CommonHeader request = current.get();
		if (request == null) {
			return new CommonHeader(StringUtils.EMPTY, StringUtils.EMPTY,0L);
		}
		return request;
	}
}

public class HttpUtil {
	/**
	 * 獲取請求頭信息
	 *
	 * @param request
	 * @return
	 */
	public static CommonHeader getCommonHeader(HttpServletRequest request) {
		String UID = request.getHeader("uid");
		Long uid = null;
		if (StringUtils.isNotBlank(UID)) {
			uid = Long.parseLong(UID);
		}
		return new CommonHeader(HttpUtil.getIp(request), request.getHeader("deviceId"), uid);
	}

	/**
	 * 獲取IP
	 *
	 * @param request
	 * @return
	 */
	public static String getIp(HttpServletRequest request) {
		String ip = request.getHeader("X-Forwarded-For");

		if (null != ip && !"".equals(ip.trim()) && !"unknown".equalsIgnoreCase(ip)) {
			int index = ip.indexOf(',');
			if (index != -1) {
				return ip.substring(0, index);
			} else {
				return ip;
			}
		}
		ip = request.getHeader("X-Real-IP");
		if (null != ip && !"".equals(ip.trim()) && !"unknown".equalsIgnoreCase(ip)) {
			return ip;
		}
		return request.getRemoteAddr();
	}
}

/**
 * 請求頭處理
 *
 * @author yangfei
 */
@Component
public class BaseInterceptor extends HandlerInterceptorAdapter {

	private static final org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger(BaseInterceptor.class);


	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {
		RequestWrap.getThreadLocal().set(HttpUtil.getCommonHeader(request));
		return true;
	}

	@Override
	public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
			ModelAndView modelAndView) throws Exception {
	}

	@Override
	public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
			throws Exception {
		RequestWrap.getThreadLocal().remove();
	}

	@Override
	public void afterConcurrentHandlingStarted(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {
	}
}

/**
 * 獲取用戶基礎(chǔ)信息
 */
@PostMapping(value = "/user/info")
public Response<UserInfo> getUserInfo() {
	return userManager.getUserInfo(RequestWrap.getUid());
}