diff --git a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackNetworkManager.java b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackNetworkManager.java
index 3491450..c028331 100644
--- a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackNetworkManager.java
+++ b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackNetworkManager.java
@@ -99,7 +99,6 @@
 
     private static final String ERR_NULL_NETWORK  = "OpenStack network cannot be null";
     private static final String ERR_NULL_NETWORK_ID  = "OpenStack network ID cannot be null";
-    private static final String ERR_NULL_NETWORK_NAME  = "OpenStack network name cannot be null";
     private static final String ERR_NULL_SUBNET = "OpenStack subnet cannot be null";
     private static final String ERR_NULL_SUBNET_ID = "OpenStack subnet ID cannot be null";
     private static final String ERR_NULL_SUBNET_NET_ID = "OpenStack subnet network ID cannot be null";
@@ -108,9 +107,7 @@
     private static final String ERR_NULL_PORT_ID = "OpenStack port ID cannot be null";
     private static final String ERR_NULL_PORT_NET_ID = "OpenStack port network ID cannot be null";
 
-    private static final String ERR_NOT_FOUND = " does not exist";
     private static final String ERR_IN_USE = " still in use";
-    private static final String ERR_DUPLICATE = " already exists";
 
     private static final int PREFIX_LENGTH = 32;
 
@@ -331,7 +328,6 @@
                             .filter(p -> p.getId().contains(portName.substring(3)))
                             .findFirst();
                     return osPort.orElse(null);
-
                 case DIRECT:
                     //Additional prefixes will be added
                     osPort = osNetworkStore.ports()
@@ -340,7 +336,6 @@
                             .filter(p -> Objects.requireNonNull(getIntfNameFromPciAddress(p)).equals(portName))
                             .findFirst();
                     return osPort.orElse(null);
-
                 default:
                     return null;
             }
@@ -532,11 +527,10 @@
             log.info("Updated external peer router map {}",
                     externalPeerRouterMap.get(ipAddress.toString()).value().toString());
         } catch (Exception e) {
-            log.error("Exception occurred because of {}", e.toString());
+            log.error("Exception occurred because of {}", e);
         }
     }
 
-
     @Override
     public void updateExternalPeerRouter(IpAddress ipAddress, MacAddress macAddress, VlanId vlanId) {
         try {
@@ -548,7 +542,7 @@
                             .build());
 
         } catch (Exception e) {
-            log.error("Exception occurred because of {}", e.toString());
+            log.error("Exception occurred because of {}", e);
         }
     }
 
@@ -577,7 +571,7 @@
                             .vlanId(vlanId).build());
 
         } catch (Exception e) {
-            log.error("Exception occurred because of {}", e.toString());
+            log.error("Exception occurred because of {}", e);
         }
     }