private void endFunctionService() {
    Object top = stack.pop();
    if (!(top instanceof FunctionServiceCreation)) {
      throw new CacheXmlException(
          "Expected a FunctionServiceCreation instance");
    }
    FunctionServiceCreation fsc = (FunctionServiceCreation) top;
    cache.setFunctionServiceCreation(fsc);
  }
When we have finished a FunctionService element, we create the object and push it onto stack
geode-core/src/main/java/org/apache/geode/internal/cache/xmlcache/CacheXmlParser.java