spring带的工具方法
/** HTML转义 **/
String s = HtmlUtils.htmlEscape("<div>hello world</div><p> </p>");
System.out.println(s);
String s2 = HtmlUtils.htmlUnescape(s);
System.out.println(s2);
<div>hello world</div><p>&nbsp;</p>
<div>hello world</div><p> </p>