diff --git a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/BindingHostId.java b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/BindingHostId.java
index c715d08..7dca32d 100644
--- a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/BindingHostId.java
+++ b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/BindingHostId.java
@@ -49,7 +49,7 @@
 
     @Override
     public int hashCode() {
-        return Objects.hash(bindingHostId);
+        return bindingHostId.hashCode();
     }
 
     @Override
diff --git a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/PhysicalNetwork.java b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/PhysicalNetwork.java
index e96e666..30631d2 100644
--- a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/PhysicalNetwork.java
+++ b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/PhysicalNetwork.java
@@ -53,7 +53,7 @@
 
     @Override
     public int hashCode() {
-        return Objects.hash(physicalNetwork);
+        return physicalNetwork.hashCode();
     }
 
     @Override
diff --git a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SecurityGroup.java b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SecurityGroup.java
index 9ec1dc6..33ddcbf 100644
--- a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SecurityGroup.java
+++ b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SecurityGroup.java
@@ -52,7 +52,7 @@
 
     @Override
     public int hashCode() {
-        return Objects.hash(securityGroup);
+        return securityGroup.hashCode();
     }
 
     @Override
diff --git a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SegmentationId.java b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SegmentationId.java
index a076265..651ebd8 100644
--- a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SegmentationId.java
+++ b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SegmentationId.java
@@ -53,7 +53,7 @@
 
     @Override
     public int hashCode() {
-        return Objects.hash(segmentationId);
+        return segmentationId.hashCode();
     }
 
     @Override
diff --git a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SubnetId.java b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SubnetId.java
index 4bcc332..eb93d15 100644
--- a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SubnetId.java
+++ b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/SubnetId.java
@@ -53,7 +53,7 @@
 
     @Override
     public int hashCode() {
-        return Objects.hash(subnetId);
+        return subnetId.hashCode();
     }
 
     @Override
diff --git a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/TenantId.java b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/TenantId.java
index c4d99e4..0e7c941 100644
--- a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/TenantId.java
+++ b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/TenantId.java
@@ -53,7 +53,7 @@
 
     @Override
     public int hashCode() {
-        return Objects.hash(tenantId);
+        return tenantId.hashCode();
     }
 
     @Override
diff --git a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/TenantNetworkId.java b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/TenantNetworkId.java
index fbb9e48..8680d28 100644
--- a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/TenantNetworkId.java
+++ b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/TenantNetworkId.java
@@ -52,7 +52,7 @@
 
     @Override
     public int hashCode() {
-        return Objects.hash(networkId);
+        return networkId.hashCode();
     }
 
     @Override
diff --git a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/VirtualPortId.java b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/VirtualPortId.java
index 3038bdf..a386348 100644
--- a/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/VirtualPortId.java
+++ b/apps/vtn/vtnrsc/src/main/java/org/onosproject/vtnrsc/VirtualPortId.java
@@ -46,7 +46,7 @@
 
     @Override
     public int hashCode() {
-        return Objects.hash(portId);
+        return portId.hashCode();
     }
 
     @Override