优化代码，防止NPE

src/main/java/cn/quantgroup/xyqb/session/XyqbSessionContextHolder.java

@@ -12,6 +12,7 @@ import org.springframework.web.context.request.RequestContextHolder;
 import org.springframework.web.context.request.ServletRequestAttributes;
 
 import javax.servlet.http.HttpServletRequest;
+import java.util.Objects;
 
 /**
  * Created by Miraculous on 2016/12/29.
@@ -40,7 +41,7 @@ public class XyqbSessionContextHolder {
   }
 
   public static SessionStruct getXSessionFromRedis(String token){
-    if (token == null || token.length() != 36) {
+    if (Objects.isNull(token) || token.length() != 36 || Objects.isNull(redisTemplate)) {
       return null;
     }
     String result = redisTemplate.opsForValue().get(Constants.Session.USER_SESSION_CACHE + token);