[bugfix] NullPointerException in IntrospectionEndpoint.post when the Authorization header is missing

Author: TakahikoKawasaki

src/main/java/com/authlete/jaxrs/server/api/IntrospectionEndpoint.java

@@ -77,7 +77,7 @@ public Response post(
         BasicCredentials credentials = BasicCredentials.parse(authorization);
 
         // Fetch the information about the resource server from DB.
-        ResourceServerEntity rsEntity = ResourceServerDao.get(credentials.getUserId());
+        ResourceServerEntity rsEntity = getResourceServer(credentials);
 
         // If failed to authenticate the resource server.
         if (authenticateResourceServer(rsEntity, credentials) == false)
@@ -110,6 +110,17 @@ private Params buildParams(
     }
 
 
+    private ResourceServerEntity getResourceServer(BasicCredentials credentials)
+    {
+        if (credentials == null)
+        {
+            return null;
+        }
+
+        return ResourceServerDao.get(credentials.getUserId());
+    }
+
+
     private boolean authenticateResourceServer(
             ResourceServerEntity rsEntity, BasicCredentials credentials)
     {