diff --git a/application/src/main/java/org/thingsboard/server/controller/AlarmCommentController.java b/application/src/main/java/org/thingsboard/server/controller/AlarmCommentController.java
index b86becd132..1af3c8c8bf 100644
--- a/application/src/main/java/org/thingsboard/server/controller/AlarmCommentController.java
+++ b/application/src/main/java/org/thingsboard/server/controller/AlarmCommentController.java
@@ -38,12 +38,10 @@ import org.thingsboard.server.common.data.page.PageLink;
 import org.thingsboard.server.queue.util.TbCoreComponent;
 import org.thingsboard.server.service.entitiy.alarm.TbAlarmCommentService;
 import org.thingsboard.server.service.security.permission.Operation;
-import org.thingsboard.server.service.security.permission.Resource;
 
 import static org.thingsboard.server.controller.ControllerConstants.ALARM_COMMENT_ID_PARAM_DESCRIPTION;
 import static org.thingsboard.server.controller.ControllerConstants.ALARM_COMMENT_SORT_PROPERTY_ALLOWABLE_VALUES;
 import static org.thingsboard.server.controller.ControllerConstants.ALARM_ID_PARAM_DESCRIPTION;
-import static org.thingsboard.server.controller.ControllerConstants.ALARM_SORT_PROPERTY_ALLOWABLE_VALUES;
 import static org.thingsboard.server.controller.ControllerConstants.PAGE_DATA_PARAMETERS;
 import static org.thingsboard.server.controller.ControllerConstants.PAGE_NUMBER_DESCRIPTION;
 import static org.thingsboard.server.controller.ControllerConstants.PAGE_SIZE_DESCRIPTION;
diff --git a/application/src/main/java/org/thingsboard/server/service/entitiy/alarm/TbAlarmCommentService.java b/application/src/main/java/org/thingsboard/server/service/entitiy/alarm/TbAlarmCommentService.java
index 74f207138e..d8bb798d49 100644
--- a/application/src/main/java/org/thingsboard/server/service/entitiy/alarm/TbAlarmCommentService.java
+++ b/application/src/main/java/org/thingsboard/server/service/entitiy/alarm/TbAlarmCommentService.java
@@ -19,7 +19,6 @@ import org.thingsboard.server.common.data.User;
 import org.thingsboard.server.common.data.alarm.Alarm;
 import org.thingsboard.server.common.data.alarm.AlarmComment;
 import org.thingsboard.server.common.data.exception.ThingsboardException;
-import org.thingsboard.server.common.data.id.TenantId;
 
 public interface TbAlarmCommentService {
     AlarmComment saveAlarmComment(Alarm alarm, AlarmComment alarmComment, User user) throws ThingsboardException;
diff --git a/application/src/test/java/org/thingsboard/server/controller/BaseAlarmCommentControllerTest.java b/application/src/test/java/org/thingsboard/server/controller/BaseAlarmCommentControllerTest.java
index 8aba871651..337abee74f 100644
--- a/application/src/test/java/org/thingsboard/server/controller/BaseAlarmCommentControllerTest.java
+++ b/application/src/test/java/org/thingsboard/server/controller/BaseAlarmCommentControllerTest.java
@@ -25,7 +25,6 @@ import org.junit.Before;
 import org.junit.Test;
 import org.mockito.AdditionalAnswers;
 import org.mockito.Mockito;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Primary;
 import org.springframework.test.context.ContextConfiguration;
diff --git a/application/src/test/java/org/thingsboard/server/service/entitiy/alarm/DefaultTbAlarmServiceTest.java b/application/src/test/java/org/thingsboard/server/service/entitiy/alarm/DefaultTbAlarmServiceTest.java
index 32a270acb4..bea64f12af 100644
--- a/application/src/test/java/org/thingsboard/server/service/entitiy/alarm/DefaultTbAlarmServiceTest.java
+++ b/application/src/test/java/org/thingsboard/server/service/entitiy/alarm/DefaultTbAlarmServiceTest.java
@@ -27,7 +27,6 @@ import org.springframework.test.context.junit4.SpringRunner;
 import org.thingsboard.server.cluster.TbClusterService;
 import org.thingsboard.server.common.data.User;
 import org.thingsboard.server.common.data.alarm.Alarm;
-import org.thingsboard.server.common.data.alarm.AlarmComment;
 import org.thingsboard.server.common.data.alarm.AlarmStatus;
 import org.thingsboard.server.common.data.exception.ThingsboardException;
 import org.thingsboard.server.common.data.id.UserId;
diff --git a/common/dao-api/src/main/java/org/thingsboard/server/dao/alarm/AlarmCommentService.java b/common/dao-api/src/main/java/org/thingsboard/server/dao/alarm/AlarmCommentService.java
index fbc2b29b6b..d4ffee4169 100644
--- a/common/dao-api/src/main/java/org/thingsboard/server/dao/alarm/AlarmCommentService.java
+++ b/common/dao-api/src/main/java/org/thingsboard/server/dao/alarm/AlarmCommentService.java
@@ -23,7 +23,6 @@ import org.thingsboard.server.common.data.id.AlarmId;
 import org.thingsboard.server.common.data.id.TenantId;
 import org.thingsboard.server.common.data.page.PageData;
 import org.thingsboard.server.common.data.page.PageLink;
-import org.thingsboard.server.dao.entity.EntityDaoService;
 
 public interface AlarmCommentService {
     AlarmComment createOrUpdateAlarmComment(TenantId tenantId, AlarmComment alarmComment);
diff --git a/dao/src/main/java/org/thingsboard/server/dao/alarm/BaseAlarmCommentService.java b/dao/src/main/java/org/thingsboard/server/dao/alarm/BaseAlarmCommentService.java
index 3984efeca0..7cc547536a 100644
--- a/dao/src/main/java/org/thingsboard/server/dao/alarm/BaseAlarmCommentService.java
+++ b/dao/src/main/java/org/thingsboard/server/dao/alarm/BaseAlarmCommentService.java
@@ -22,21 +22,17 @@ import com.google.common.util.concurrent.ListenableFuture;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
-import org.thingsboard.server.common.data.EntityType;
 import org.thingsboard.server.common.data.alarm.AlarmComment;
 import org.thingsboard.server.common.data.alarm.AlarmCommentInfo;
 import org.thingsboard.server.common.data.alarm.AlarmCommentType;
 import org.thingsboard.server.common.data.id.AlarmCommentId;
 import org.thingsboard.server.common.data.id.AlarmId;
-import org.thingsboard.server.common.data.id.EntityId;
-import org.thingsboard.server.common.data.id.HasId;
 import org.thingsboard.server.common.data.id.TenantId;
 import org.thingsboard.server.common.data.page.PageData;
 import org.thingsboard.server.common.data.page.PageLink;
 import org.thingsboard.server.dao.entity.AbstractEntityService;
 import org.thingsboard.server.dao.service.DataValidator;
 
-import java.util.Optional;
 import java.util.UUID;
 
 import static org.thingsboard.server.dao.service.Validator.validateId;
diff --git a/dao/src/main/java/org/thingsboard/server/dao/audit/AuditLogServiceImpl.java b/dao/src/main/java/org/thingsboard/server/dao/audit/AuditLogServiceImpl.java
index 1d42dc5a26..e7f57b0eb0 100644
--- a/dao/src/main/java/org/thingsboard/server/dao/audit/AuditLogServiceImpl.java
+++ b/dao/src/main/java/org/thingsboard/server/dao/audit/AuditLogServiceImpl.java
@@ -46,7 +46,6 @@ import org.thingsboard.server.common.data.page.TimePageLink;
 import org.thingsboard.server.common.data.relation.EntityRelation;
 import org.thingsboard.server.common.data.rule.RuleChainMetaData;
 import org.thingsboard.server.common.data.security.DeviceCredentials;
-import org.thingsboard.server.dao.alarm.AlarmCommentService;
 import org.thingsboard.server.dao.audit.sink.AuditLogSink;
 import org.thingsboard.server.dao.device.provision.ProvisionRequest;
 import org.thingsboard.server.dao.entity.EntityService;
diff --git a/dao/src/main/java/org/thingsboard/server/dao/model/sql/AlarmCommentInfoEntity.java b/dao/src/main/java/org/thingsboard/server/dao/model/sql/AlarmCommentInfoEntity.java
index bc9c5841c5..1d19ec9388 100644
--- a/dao/src/main/java/org/thingsboard/server/dao/model/sql/AlarmCommentInfoEntity.java
+++ b/dao/src/main/java/org/thingsboard/server/dao/model/sql/AlarmCommentInfoEntity.java
@@ -19,9 +19,6 @@ import lombok.Data;
 import lombok.EqualsAndHashCode;
 import org.thingsboard.server.common.data.alarm.AlarmCommentInfo;
 
-import java.util.HashMap;
-import java.util.Map;
-
 @Data
 @EqualsAndHashCode(callSuper = true)
 public class AlarmCommentInfoEntity extends AbstractAlarmCommentEntity<AlarmCommentInfo> {
diff --git a/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/util/EntitiesFieldsAsyncLoader.java b/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/util/EntitiesFieldsAsyncLoader.java
index 4c7647a321..245b671cf5 100644
--- a/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/util/EntitiesFieldsAsyncLoader.java
+++ b/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/util/EntitiesFieldsAsyncLoader.java
@@ -22,7 +22,6 @@ import org.thingsboard.rule.engine.api.TbContext;
 import org.thingsboard.rule.engine.api.TbNodeException;
 import org.thingsboard.server.common.data.BaseData;
 import org.thingsboard.server.common.data.EntityFieldsData;
-import org.thingsboard.server.common.data.id.AlarmCommentId;
 import org.thingsboard.server.common.data.id.AlarmId;
 import org.thingsboard.server.common.data.id.AssetId;
 import org.thingsboard.server.common.data.id.CustomerId;
diff --git a/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/util/TenantIdLoader.java b/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/util/TenantIdLoader.java
index f8eb5bc848..b687246789 100644
--- a/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/util/TenantIdLoader.java
+++ b/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/util/TenantIdLoader.java
@@ -18,8 +18,6 @@ package org.thingsboard.rule.engine.util;
 import org.thingsboard.rule.engine.api.TbContext;
 import org.thingsboard.server.common.data.EntityType;
 import org.thingsboard.server.common.data.HasTenantId;
-import org.thingsboard.server.common.data.alarm.AlarmComment;
-import org.thingsboard.server.common.data.id.AlarmCommentId;
 import org.thingsboard.server.common.data.id.AlarmId;
 import org.thingsboard.server.common.data.id.ApiUsageStateId;
 import org.thingsboard.server.common.data.id.AssetId;
diff --git a/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/util/TenantIdLoaderTest.java b/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/util/TenantIdLoaderTest.java
index 6ac3f58925..08081ff961 100644
--- a/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/util/TenantIdLoaderTest.java
+++ b/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/util/TenantIdLoaderTest.java
@@ -41,11 +41,9 @@ import org.thingsboard.server.common.data.TbResource;
 import org.thingsboard.server.common.data.TenantProfile;
 import org.thingsboard.server.common.data.User;
 import org.thingsboard.server.common.data.alarm.Alarm;
-import org.thingsboard.server.common.data.alarm.AlarmComment;
 import org.thingsboard.server.common.data.asset.Asset;
 import org.thingsboard.server.common.data.asset.AssetProfile;
 import org.thingsboard.server.common.data.edge.Edge;
-import org.thingsboard.server.common.data.id.AlarmId;
 import org.thingsboard.server.common.data.id.AssetProfileId;
 import org.thingsboard.server.common.data.id.DeviceProfileId;
 import org.thingsboard.server.common.data.id.EntityId;