diff --git a/incubator/store/src/main/java/org/onosproject/incubator/store/resource/impl/DistributedLabelResourceStore.java b/incubator/store/src/main/java/org/onosproject/incubator/store/resource/impl/DistributedLabelResourceStore.java
index b82fa92..740b6aa 100644
--- a/incubator/store/src/main/java/org/onosproject/incubator/store/resource/impl/DistributedLabelResourceStore.java
+++ b/incubator/store/src/main/java/org/onosproject/incubator/store/resource/impl/DistributedLabelResourceStore.java
@@ -103,7 +103,7 @@
     private static final Serializer SERIALIZER = Serializer
             .using(new KryoNamespace.Builder().register(KryoNamespaces.API)
                     .register(LabelResourceEvent.class)
-                    .register(LabelResourcePool.class).register(DeviceId.class)
+                    .register(LabelResourcePool.class)
                     .register(LabelResourceRequest.class)
                     .register(LabelResourceRequest.Type.class)
                     .register(LabelResourceEvent.Type.class)
@@ -197,7 +197,7 @@
     }
 
     private boolean create(LabelResourcePool pool) {
-        Device device = (Device) deviceService.getDevice(pool.deviceId());
+        Device device = deviceService.getDevice(pool.deviceId());
         if (device == null) {
             return false;
         }
@@ -238,7 +238,7 @@
 
     @Override
     public boolean destroyDevicePool(DeviceId deviceId) {
-        Device device = (Device) deviceService.getDevice(deviceId);
+        Device device = deviceService.getDevice(deviceId);
         if (device == null) {
             return false;
         }
@@ -280,7 +280,7 @@
     @Override
     public Collection<LabelResource> applyFromDevicePool(DeviceId deviceId,
                                                          long applyNum) {
-        Device device = (Device) deviceService.getDevice(deviceId);
+        Device device = deviceService.getDevice(deviceId);
         if (device == null) {
             return Collections.emptyList();
         }
@@ -317,13 +317,13 @@
             return Collections.emptyList();
         }
         LabelResourcePool pool = poolOld.value();
-        Collection<LabelResource> result = new HashSet<LabelResource>();
+        Collection<LabelResource> result = new HashSet<>();
         long freeNum = this.getFreeNumOfDevicePool(deviceId);
         if (applyNum > freeNum) {
             log.info("the free number of the label resource pool of deviceId {} is not enough.");
             return Collections.emptyList();
         }
-        Set<LabelResource> releaseLabels = new HashSet<LabelResource>(pool.releaseLabelId());
+        Set<LabelResource> releaseLabels = new HashSet<>(pool.releaseLabelId());
         long tmp = releaseLabels.size() > applyNum ? applyNum : releaseLabels
                 .size();
         LabelResource resource = null;
@@ -364,8 +364,8 @@
         Set<DeviceId> deviceIdSet = maps.keySet();
         LabelResourceRequest request = null;
         for (Iterator<DeviceId> it = deviceIdSet.iterator(); it.hasNext();) {
-            DeviceId deviceId = (DeviceId) it.next();
-            Device device = (Device) deviceService.getDevice(deviceId);
+            DeviceId deviceId = it.next();
+            Device device = deviceService.getDevice(deviceId);
             if (device == null) {
                 continue;
             }
@@ -410,7 +410,7 @@
             log.info("the label resource pool of device id {} does not exist");
             return false;
         }
-        Set<LabelResource> storeSet = new HashSet<LabelResource>(pool.releaseLabelId());
+        Set<LabelResource> storeSet = new HashSet<>(pool.releaseLabelId());
         LabelResource labelResource = null;
         long realReleasedNum = 0;
         for (Iterator<LabelResource> it = release.iterator(); it.hasNext();) {
@@ -486,7 +486,7 @@
 
     @Override
     public boolean releaseToGlobalPool(Set<LabelResourceId> release) {
-        Set<LabelResource> set = new HashSet<LabelResource>();
+        Set<LabelResource> set = new HashSet<>();
         DefaultLabelResource resource = null;
         for (LabelResourceId labelResource : release) {
             resource = new DefaultLabelResource(DeviceId.deviceId(GLOBAL_RESOURCE_POOL_DEVICE_ID),
diff --git a/incubator/store/src/main/java/org/onosproject/incubator/store/virtual/impl/DistributedVirtualNetworkStore.java b/incubator/store/src/main/java/org/onosproject/incubator/store/virtual/impl/DistributedVirtualNetworkStore.java
index f4eedc4..1452dfc 100644
--- a/incubator/store/src/main/java/org/onosproject/incubator/store/virtual/impl/DistributedVirtualNetworkStore.java
+++ b/incubator/store/src/main/java/org/onosproject/incubator/store/virtual/impl/DistributedVirtualNetworkStore.java
@@ -123,7 +123,7 @@
     private static final Serializer SERIALIZER = Serializer
             .using(new KryoNamespace.Builder().register(KryoNamespaces.API)
                            .register(TenantId.class)
-                           .register(NetworkId.class).register(DeviceId.class)
+                           .register(NetworkId.class)
                            .register(VirtualNetwork.class)
                            .register(DefaultVirtualNetwork.class)
                            .register(VirtualDevice.class)
@@ -132,7 +132,6 @@
                            .register(DefaultVirtualLink.class)
                            .register(VirtualPort.class)
                            .register(DefaultVirtualPort.class)
-                           .register(DeviceId.class)
                            .register(Device.class)
                            .register(DefaultDevice.class)
                            .register(DefaultPort.class)
@@ -284,9 +283,9 @@
 
             tenantIdNetworkIdSetMap.compute(virtualNetwork.tenantId(), (id, existingNetworkIds) -> {
                 if (existingNetworkIds == null || existingNetworkIds.isEmpty()) {
-                    return new HashSet<NetworkId>();
+                    return new HashSet<>();
                 } else {
-                    return new HashSet<NetworkId>(Sets.difference(existingNetworkIds, networkIdSet));
+                    return new HashSet<>(Sets.difference(existingNetworkIds, networkIdSet));
                 }
             });
         }
@@ -332,9 +331,9 @@
         if (deviceIdSet != null) {
             networkIdDeviceIdSetMap.compute(networkId, (id, existingDeviceIds) -> {
                 if (existingDeviceIds == null || existingDeviceIds.isEmpty()) {
-                    return new HashSet<DeviceId>();
+                    return new HashSet<>();
                 } else {
-                    return new HashSet<DeviceId>(Sets.difference(existingDeviceIds, deviceIdSet));
+                    return new HashSet<>(Sets.difference(existingDeviceIds, deviceIdSet));
                 }
             });
 
@@ -398,9 +397,9 @@
         if (virtualLinkSet != null) {
             networkIdVirtualLinkSetMap.compute(networkId, (id, existingVirtualLinks) -> {
                 if (existingVirtualLinks == null || existingVirtualLinks.isEmpty()) {
-                    return new HashSet<VirtualLink>();
+                    return new HashSet<>();
                 } else {
-                    return new HashSet<VirtualLink>(Sets.difference(existingVirtualLinks, virtualLinkSet));
+                    return new HashSet<>(Sets.difference(existingVirtualLinks, virtualLinkSet));
                 }
             });
         }
@@ -436,9 +435,9 @@
         if (virtualPortSet != null) {
             networkIdVirtualPortSetMap.compute(networkId, (id, existingVirtualPorts) -> {
                 if (existingVirtualPorts == null || existingVirtualPorts.isEmpty()) {
-                    return new HashSet<VirtualPort>();
+                    return new HashSet<>();
                 } else {
-                    return new HashSet<VirtualPort>(Sets.difference(existingVirtualPorts, virtualPortSet));
+                    return new HashSet<>(Sets.difference(existingVirtualPorts, virtualPortSet));
                 }
             });
         }