@Test public void testQuoting() throws Exception {

  assertEquals("ab&lt;cd", HtmlQuoting.quoteHtmlChars("ab<cd"));
  assertEquals("ab&gt;", HtmlQuoting.quoteHtmlChars("ab>"));
  assertEquals("&amp;&amp;&amp;", HtmlQuoting.quoteHtmlChars("&&&"));
  assertEquals(" &apos;\n", HtmlQuoting.quoteHtmlChars(" '\n"));
  assertEquals("&quot;", HtmlQuoting.quoteHtmlChars("\""));
  assertEquals(null, HtmlQuoting.quoteHtmlChars(null));
}