title: Jsoup: get all heading tags
body: <p>I'm trying to parse an html document with Jsoup to get all heading tags. In addition I need to  group the heading tags as [h1] [h2] etc...</p>
  
  <pre><code>     hh = doc.select("h[0-6]");
  </code></pre>
  
  <p>but this give me an empty array.</p>