diff --git a/dao/src/main/java/org/thingsboard/server/dao/sql/relation/JpaRelationDao.java b/dao/src/main/java/org/thingsboard/server/dao/sql/relation/JpaRelationDao.java
index 7e4b41702e..31125a0791 100644
--- a/dao/src/main/java/org/thingsboard/server/dao/sql/relation/JpaRelationDao.java
+++ b/dao/src/main/java/org/thingsboard/server/dao/sql/relation/JpaRelationDao.java
@@ -34,7 +34,11 @@ import org.thingsboard.server.dao.relation.RelationDao;
 import org.thingsboard.server.dao.sql.JpaAbstractDaoListeningExecutorService;
 import org.thingsboard.server.dao.util.SqlDao;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
 import java.util.stream.Collectors;
 
 /**