@Test
void find()
{

    RegexTool tool = new RegexTool();
    List<RegexResult> result =
        tool.find("<h1><span>header</span></h1> whatever", "<[hH][12].*?><span>(.*?)</span></[hH][12]>");
    assertEquals(2, result.size());
    assertEquals("<h1><span>header</span></h1>", result.get(0).getGroup());
    assertEquals(0, result.get(0).getStart());
    assertEquals(28, result.get(0).getEnd());
    assertEquals("header", result.get(1).getGroup());
    assertEquals(10, result.get(1).getStart());
    assertEquals(16, result.get(1).getEnd());
}