diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/apache-httpclient/ApiClient.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/apache-httpclient/ApiClient.mustache
index dadec3c2cce..371f8ee7268 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/apache-httpclient/ApiClient.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/apache-httpclient/ApiClient.mustache
@@ -228,6 +228,7 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
    */
   public ApiClient setBasePath(String basePath) {
     this.basePath = basePath;
+    this.serverIndex = null;
     return this;
   }
 
diff --git a/samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/ApiClient.java
index 686ad20b951..754393e13a0 100644
--- a/samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/ApiClient.java
@@ -193,6 +193,7 @@ public class ApiClient extends JavaTimeFormatter {
    */
   public ApiClient setBasePath(String basePath) {
     this.basePath = basePath;
+    this.serverIndex = null;
     return this;
   }