diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/restclient/ApiClient.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/restclient/ApiClient.mustache
index 3dd26153003f..a69f86b4b9be 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/restclient/ApiClient.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/restclient/ApiClient.mustache
@@ -389,10 +389,20 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
      * @param accessToken the access token
      */
     public void setAccessToken(String accessToken) {
+        setAccessToken(() -> accessToken);
+    }
+
+    /**
+     * Helper method to set the supplier of access tokens for OAuth2 authentication.
+     *
+     * @param tokenSupplier The supplier of access tokens
+     * @return ApiClient this client
+     */
+    public ApiClient setAccessToken(Supplier<String> tokenSupplier) {
         for (Authentication auth : authentications.values()) {
             if (auth instanceof OAuth) {
-                ((OAuth) auth).setAccessToken(accessToken);
-                return;
+                ((OAuth) auth).setAccessToken(tokenSupplier);
+                return this;
             }
         }
         throw new RuntimeException("No OAuth2 authentication configured!");
diff --git a/samples/client/petstore/java/restclient-swagger2/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/restclient-swagger2/src/main/java/org/openapitools/client/ApiClient.java
index bdad8856c14b..09e69f4c9c88 100644
--- a/samples/client/petstore/java/restclient-swagger2/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/restclient-swagger2/src/main/java/org/openapitools/client/ApiClient.java
@@ -386,10 +386,20 @@ public void setApiKeyPrefix(String apiKeyPrefix) {
      * @param accessToken the access token
      */
     public void setAccessToken(String accessToken) {
+        setAccessToken(() -> accessToken);
+    }
+
+    /**
+     * Helper method to set the supplier of access tokens for OAuth2 authentication.
+     *
+     * @param tokenSupplier The supplier of access tokens
+     * @return ApiClient this client
+     */
+    public ApiClient setAccessToken(Supplier<String> tokenSupplier) {
         for (Authentication auth : authentications.values()) {
             if (auth instanceof OAuth) {
-                ((OAuth) auth).setAccessToken(accessToken);
-                return;
+                ((OAuth) auth).setAccessToken(tokenSupplier);
+                return this;
             }
         }
         throw new RuntimeException("No OAuth2 authentication configured!");
diff --git a/samples/client/petstore/java/restclient-useSingleRequestParameter-static/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/restclient-useSingleRequestParameter-static/src/main/java/org/openapitools/client/ApiClient.java
index bdad8856c14b..09e69f4c9c88 100644
--- a/samples/client/petstore/java/restclient-useSingleRequestParameter-static/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/restclient-useSingleRequestParameter-static/src/main/java/org/openapitools/client/ApiClient.java
@@ -386,10 +386,20 @@ public void setApiKeyPrefix(String apiKeyPrefix) {
      * @param accessToken the access token
      */
     public void setAccessToken(String accessToken) {
+        setAccessToken(() -> accessToken);
+    }
+
+    /**
+     * Helper method to set the supplier of access tokens for OAuth2 authentication.
+     *
+     * @param tokenSupplier The supplier of access tokens
+     * @return ApiClient this client
+     */
+    public ApiClient setAccessToken(Supplier<String> tokenSupplier) {
         for (Authentication auth : authentications.values()) {
             if (auth instanceof OAuth) {
-                ((OAuth) auth).setAccessToken(accessToken);
-                return;
+                ((OAuth) auth).setAccessToken(tokenSupplier);
+                return this;
             }
         }
         throw new RuntimeException("No OAuth2 authentication configured!");
diff --git a/samples/client/petstore/java/restclient-useSingleRequestParameter/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/restclient-useSingleRequestParameter/src/main/java/org/openapitools/client/ApiClient.java
index bdad8856c14b..09e69f4c9c88 100644
--- a/samples/client/petstore/java/restclient-useSingleRequestParameter/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/restclient-useSingleRequestParameter/src/main/java/org/openapitools/client/ApiClient.java
@@ -386,10 +386,20 @@ public void setApiKeyPrefix(String apiKeyPrefix) {
      * @param accessToken the access token
      */
     public void setAccessToken(String accessToken) {
+        setAccessToken(() -> accessToken);
+    }
+
+    /**
+     * Helper method to set the supplier of access tokens for OAuth2 authentication.
+     *
+     * @param tokenSupplier The supplier of access tokens
+     * @return ApiClient this client
+     */
+    public ApiClient setAccessToken(Supplier<String> tokenSupplier) {
         for (Authentication auth : authentications.values()) {
             if (auth instanceof OAuth) {
-                ((OAuth) auth).setAccessToken(accessToken);
-                return;
+                ((OAuth) auth).setAccessToken(tokenSupplier);
+                return this;
             }
         }
         throw new RuntimeException("No OAuth2 authentication configured!");
diff --git a/samples/client/petstore/java/restclient/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/restclient/src/main/java/org/openapitools/client/ApiClient.java
index bdad8856c14b..09e69f4c9c88 100644
--- a/samples/client/petstore/java/restclient/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/restclient/src/main/java/org/openapitools/client/ApiClient.java
@@ -386,10 +386,20 @@ public void setApiKeyPrefix(String apiKeyPrefix) {
      * @param accessToken the access token
      */
     public void setAccessToken(String accessToken) {
+        setAccessToken(() -> accessToken);
+    }
+
+    /**
+     * Helper method to set the supplier of access tokens for OAuth2 authentication.
+     *
+     * @param tokenSupplier The supplier of access tokens
+     * @return ApiClient this client
+     */
+    public ApiClient setAccessToken(Supplier<String> tokenSupplier) {
         for (Authentication auth : authentications.values()) {
             if (auth instanceof OAuth) {
-                ((OAuth) auth).setAccessToken(accessToken);
-                return;
+                ((OAuth) auth).setAccessToken(tokenSupplier);
+                return this;
             }
         }
         throw new RuntimeException("No OAuth2 authentication configured!");