diff --git a/dubbo-registry/dubbo-registry-api/src/main/java/org/apache/dubbo/registry/client/event/listener/ServiceInstancesChangedListener.java b/dubbo-registry/dubbo-registry-api/src/main/java/org/apache/dubbo/registry/client/event/listener/ServiceInstancesChangedListener.java
index e069ead88c1..8daf825df8f 100644
--- a/dubbo-registry/dubbo-registry-api/src/main/java/org/apache/dubbo/registry/client/event/listener/ServiceInstancesChangedListener.java
+++ b/dubbo-registry/dubbo-registry-api/src/main/java/org/apache/dubbo/registry/client/event/listener/ServiceInstancesChangedListener.java
@@ -65,8 +65,6 @@
 import static org.apache.dubbo.metadata.RevisionResolver.EMPTY_REVISION;
 import static org.apache.dubbo.registry.client.metadata.ServiceInstanceMetadataUtils.getExportedServicesRevision;
 
-;
-
 /**
  * TODO, refactor to move revision-metadata mapping to ServiceDiscovery. Instances should have already been mapped with metadata when reached here.
  * <p>
@@ -209,11 +207,7 @@ private synchronized void doOnEvent(ServiceInstancesChangedEvent event) {
 
             Map<Integer, Map<Set<String>, Object>> portToRevisions = protocolRevisionsToUrls.computeIfAbsent(serviceInfo.getProtocol(), k -> new HashMap<>());
             Map<Set<String>, Object> revisionsToUrls = portToRevisions.computeIfAbsent(serviceInfo.getPort(), k -> new HashMap<>());
-            Object urls = revisionsToUrls.get(revisions);
-            if (urls == null) {
-                urls = getServiceUrlsCache(revisionToInstances, revisions, serviceInfo.getProtocol(), serviceInfo.getPort());
-                revisionsToUrls.put(revisions, urls);
-            }
+            Object urls = revisionsToUrls.computeIfAbsent(revisions, k -> getServiceUrlsCache(revisionToInstances, revisions, serviceInfo.getProtocol(), serviceInfo.getPort()));
 
             List<ProtocolServiceKeyWithUrls> list = newServiceUrls.computeIfAbsent(serviceInfo.getPath(), k -> new LinkedList<>());
             list.add(new ProtocolServiceKeyWithUrls(serviceInfo.getProtocolServiceKey(), (List<URL>) urls));
@@ -255,7 +249,7 @@ public synchronized void removeListener(String serviceKey, NotifyListener notify
             notifyListeners.removeIf(listener -> listener.getNotifyListener().equals(notifyListener));
 
             // ServiceKey has no listener, remove set
-            if (notifyListeners.size() == 0) {
+            if (notifyListeners.isEmpty()) {
                 this.listeners.remove(serviceKey);
             }
         }
@@ -478,7 +472,7 @@ public boolean equals(Object o) {
 
     @Override
     public int hashCode() {
-        return Objects.hash(getClass(), getServiceNames(), listeners);
+        return Objects.hash(getClass(), getServiceNames());
     }
 
     protected class AddressRefreshRetryTask implements Runnable {