diff --git a/modules/swagger-codegen/src/main/resources/Java/libraries/retrofit/auth/OAuth.mustache b/modules/swagger-codegen/src/main/resources/Java/libraries/retrofit/auth/OAuth.mustache
index 68ee918601e..647ff141329 100644
--- a/modules/swagger-codegen/src/main/resources/Java/libraries/retrofit/auth/OAuth.mustache
+++ b/modules/swagger-codegen/src/main/resources/Java/libraries/retrofit/auth/OAuth.mustache
@@ -1,6 +1,7 @@
 package {{invokerPackage}}.auth;
 
 import static java.net.HttpURLConnection.HTTP_UNAUTHORIZED;
+import static java.net.HttpURLConnection.HTTP_FORBIDDEN;
 
 import java.io.IOException;
 import java.util.Map;
@@ -85,42 +86,55 @@ public class OAuth implements Interceptor {
             updateAccessToken(null);
         }
 
-        // Build the request
-        Builder rb = request.newBuilder();
-
-        String requestAccessToken = new String(getAccessToken());
-        try {
-            oAuthRequest = new OAuthBearerClientRequest(request.urlString())
-            .setAccessToken(requestAccessToken)
-            .buildHeaderMessage();
-        } catch (OAuthSystemException e) {
-            throw new IOException(e);
+        if (getAccessToken() != null) {
+            // Build the request
+            Builder rb = request.newBuilder();
+    
+            String requestAccessToken = new String(getAccessToken());
+            try {
+                oAuthRequest = new OAuthBearerClientRequest(request.urlString())
+                        .setAccessToken(requestAccessToken)
+                        .buildHeaderMessage();
+            } catch (OAuthSystemException e) {
+                throw new IOException(e);
+            }
+    
+            for ( Map.Entry<String, String> header : oAuthRequest.getHeaders().entrySet() ) {
+                rb.addHeader(header.getKey(), header.getValue());
+            }
+            rb.url( oAuthRequest.getLocationUri());
+    
+            //Execute the request
+            Response response = chain.proceed(rb.build());
+    
+            // 401 most likely indicates that access token has expired.
+            // Time to refresh and resend the request
+            if ( response != null && (response.code() == HTTP_UNAUTHORIZED | response.code() == HTTP_FORBIDDEN) ) {
+                if (updateAccessToken(requestAccessToken)) {
+                    return intercept( chain );
+                }
+            }
+            return response;
+        } else {
+            return chain.proceed(chain.request());
         }
-
-        for ( Map.Entry<String, String> header : oAuthRequest.getHeaders().entrySet() ) {
-            rb.addHeader(header.getKey(), header.getValue());
-        }
-        rb.url( oAuthRequest.getLocationUri());
-
-        //Execute the request
-        Response response = chain.proceed(rb.build());
-
-        // 401 most likely indicates that access token has expired.
-        // Time to refresh and resend the request
-        if ( response.code() == HTTP_UNAUTHORIZED ) {
-            updateAccessToken(requestAccessToken);
-            return intercept( chain );
-        }
-        return response;    
     }
 
-    public synchronized void updateAccessToken(String requestAccessToken) throws IOException {
+    /*
+     * Returns true if the access token has been updated
+     */
+    public synchronized boolean updateAccessToken(String requestAccessToken) throws IOException {
         if (getAccessToken() == null || getAccessToken().equals(requestAccessToken)) {    
             try {
                 OAuthJSONAccessTokenResponse accessTokenResponse = oauthClient.accessToken(this.tokenRequestBuilder.buildBodyMessage());
-                setAccessToken(accessTokenResponse.getAccessToken());
-                if (accessTokenListener != null) {
-                    accessTokenListener.notify((BasicOAuthToken) accessTokenResponse.getOAuthToken());
+                if (accessTokenResponse != null && accessTokenResponse.getAccessToken() != null) {
+                    setAccessToken(accessTokenResponse.getAccessToken());
+                    if (accessTokenListener != null) {
+                        accessTokenListener.notify((BasicOAuthToken) accessTokenResponse.getOAuthToken());
+                    }
+                    return getAccessToken().equals(requestAccessToken);
+                } else {
+                    return false;
                 }
             } catch (OAuthSystemException e) {
                 throw new IOException(e);
@@ -128,6 +142,7 @@ public class OAuth implements Interceptor {
                 throw new IOException(e);
             }
         }
+        return true;
     }
 
     public void registerAccessTokenListener(AccessTokenListener accessTokenListener) {