```java Map<String, List> map = if (map.get("good") == null) { } else { } Optional(map.get("good")) .map() .orElse() ``` ```java WrapperInfoProxy res = wrapperInfoProxyList.stream() .filter(wrapperInfoProxy -> StringUtils.equals(wrapperInfoProxy.getWrapperId(), codebase)) .findFirst() .orElseGet(WrapperInfoProxy::new); ```