In my fair scheduler web page, the resources shown of each queue is like this: "& lt;memory:65536, vCores:0& gt;"
so obviously "& lt;" should be shown as "<", bet it isn't. After reading the codes, I suppose it's because method StringEscapeUtils.escapeHtml is called twice. But I only found one place. Anyway, I modify the code, and this problem seems to be solved.