code: @Override
      public CoreExtension resolve(ExtensionId extensionId) throws ResolveException
      {
          CoreExtension extension = getCoreExtension(extensionId.getId());
  
          if (extension == null
              || (extensionId.getVersion() != null && !extension.getId().getVersion().equals(extensionId.getVersion()))) {
              throw new ExtensionNotFoundException("Could not find extension [" + extensionId + "]");
          }
  
          return extension;
      }
docs: Repository