From 9837cfbb0b4e008d976aa02a7a8c0730b4fa3514 Mon Sep 17 00:00:00 2001
From: Albumen Kevin <jhq0812@gmail.com>
Date: Wed, 26 Jul 2023 11:10:54 +0800
Subject: [PATCH] Fix register failed if re-register service discovery (#12795)

---
 .../registry/client/AbstractServiceDiscovery.java      | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/dubbo-registry/dubbo-registry-api/src/main/java/org/apache/dubbo/registry/client/AbstractServiceDiscovery.java b/dubbo-registry/dubbo-registry-api/src/main/java/org/apache/dubbo/registry/client/AbstractServiceDiscovery.java
index 9da383d771..b3b771c20e 100644
--- a/dubbo-registry/dubbo-registry-api/src/main/java/org/apache/dubbo/registry/client/AbstractServiceDiscovery.java
+++ b/dubbo-registry/dubbo-registry-api/src/main/java/org/apache/dubbo/registry/client/AbstractServiceDiscovery.java
@@ -132,11 +132,13 @@ public abstract class AbstractServiceDiscovery implements ServiceDiscovery {
         if (isDestroy) {
             return;
         }
-        ServiceInstance serviceInstance = createServiceInstance(this.metadataInfo);
-        if (!isValidInstance(serviceInstance)) {
-            return;
+        if (this.serviceInstance == null) {
+            ServiceInstance serviceInstance = createServiceInstance(this.metadataInfo);
+            if (!isValidInstance(serviceInstance)) {
+                return;
+            }
+            this.serviceInstance = serviceInstance;
         }
-        this.serviceInstance = serviceInstance;
         boolean revisionUpdated = calOrUpdateInstanceRevision(this.serviceInstance);
         if (revisionUpdated) {
             reportMetadata(this.metadataInfo);