diff --git a/apm-collector/apm-collector-storage/collector-storage-es-provider/src/main/java/org/apache/skywalking/apm/collector/storage/es/DataTTLKeeperTimer.java b/apm-collector/apm-collector-storage/collector-storage-es-provider/src/main/java/org/apache/skywalking/apm/collector/storage/es/DataTTLKeeperTimer.java
index 58d457f5c..6114a3b24 100644
--- a/apm-collector/apm-collector-storage/collector-storage-es-provider/src/main/java/org/apache/skywalking/apm/collector/storage/es/DataTTLKeeperTimer.java
+++ b/apm-collector/apm-collector-storage/collector-storage-es-provider/src/main/java/org/apache/skywalking/apm/collector/storage/es/DataTTLKeeperTimer.java
@@ -19,13 +19,23 @@
 
 package org.apache.skywalking.apm.collector.storage.es;
 
-import org.apache.skywalking.apm.collector.core.module.ModuleManager;
-import org.apache.skywalking.apm.collector.storage.StorageModule;
-import org.apache.skywalking.apm.collector.storage.dao.*;
-
 import java.util.Calendar;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
+import org.apache.skywalking.apm.collector.storage.dao.IInstanceMetricPersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.IMemoryPoolMetricPersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.IServiceReferenceMetricPersistenceDAO;
+import org.apache.skywalking.apm.collector.core.module.ModuleManager;
+import org.apache.skywalking.apm.collector.storage.StorageModule;
+import org.apache.skywalking.apm.collector.storage.dao.IApplicationComponentPersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.IApplicationMappingPersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.IApplicationReferenceMetricPersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.ICpuMetricPersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.IGCMetricPersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.IGlobalTracePersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.IMemoryMetricPersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.ISegmentCostPersistenceDAO;
+import org.apache.skywalking.apm.collector.storage.dao.ISegmentPersistenceDAO;
 
 /**
  * @author peng-yongsheng