图谱关系查询时，添加保护

src/main/java/com/diagbot/util/NeoUtil.java

@@ -244,7 +244,10 @@ public class NeoUtil {
 
     public static boolean isExist(BaseRelation relationship) {
 
-        if (null==relationship.getStatus() ||
+        if (null==relationship) {
+            return false;
+        }
+        else if (null==relationship.getStatus() ||
                 (null!=relationship.getStatus() && relationship.getStatus()==1)) {
             return true;
         }