求一段正则表达式
<div onclick=''>adfadfasdf</div><a>aaaaaaaaaaaaa</a><p>adfadfasdf</p><img src=''/>

要求只留下adfadfasdf<a>aaaaaaaaaaaaa</a>adfadfasdf<img src=''/>

过滤掉非a标签和img标签的所有其它标签但留下标签中的内容
a标签和img标签不要过滤掉HTML标记 正则表达式
[解决办法]

public static void main(String[] args) throws Exception {
String str= "<div onclick=''>adfadfasdf</div><a>aaaaaaaaaaaaa</a><p>adfadfasdf</p><img src=''/>";
str = str.replaceAll("(?is)<(?!/?(a
[解决办法]
img)).*?>", "");
System.out.println(str);
}