[Java][apache-httpclient][feign][okhttp-gson] Enable access token refresh (#17086)

* add setter of bearer token supplier

* run generate-samples.sh

* add test of bearer auth

samples/client/petstore/java/resttemplate-withXml/src/main/java/org/openapitools/client/ApiClient.java

@@ -166,18 +166,18 @@ public class ApiClient extends JavaTimeFormatter {
     }
 
     /**
-     * Helper method to set token for HTTP bearer authentication.
+     * Helper method to set access token for the first Bearer authentication.
      *
-     * @param bearerToken the token
+     * @param bearerToken Bearer token
      */
     public void setBearerToken(String bearerToken) {
         setBearerToken(() -> bearerToken);
     }
 
     /**
-     * Helper method to set the token supplier for HTTP bearer authentication.
+     * Helper method to set the supplier of access tokens for Bearer authentication.
      *
-     * @param tokenSupplier the token supplier function
+     * @param tokenSupplier The supplier of bearer tokens
      */
     public void setBearerToken(Supplier<String> tokenSupplier) {
         for (Authentication auth : authentications.values()) {

samples/client/petstore/java/resttemplate-withXml/src/main/java/org/openapitools/client/auth/HttpBearerAuth.java

@@ -14,14 +14,29 @@ public class HttpBearerAuth implements Authentication {
         this.scheme = scheme;
     }
 
+    /**
+     * Gets the token, which together with the scheme, will be sent as the value of the Authorization header.
+     *
+     * @return The bearer token
+     */
     public String getBearerToken() {
         return tokenSupplier.get();
     }
 
+    /**
+     * Sets the token, which together with the scheme, will be sent as the value of the Authorization header.
+     *
+     * @param bearerToken The bearer token to send in the Authorization header
+     */
     public void setBearerToken(String bearerToken) {
         this.tokenSupplier = () -> bearerToken;
     }
-    
+
+    /**
+     * Sets the supplier of tokens, which together with the scheme, will be sent as the value of the Authorization header.
+     *
+     * @param tokenSupplier The supplier of bearer tokens to send in the Authorization header
+     */
     public void setBearerToken(Supplier<String> tokenSupplier) {
         this.tokenSupplier = tokenSupplier;
     }