@Test
public void testGetDialog() throws Exception {

    final VoiceXmlDocument document = new VoiceXmlDocument();
    final Vxml vxml = document.getVxml();
    final Form form1 = vxml.appendChild(Form.class);
    final String id1 = "horst";
    form1.setId(id1);
    final Form form2 = vxml.appendChild(Form.class);
    final String id2 = "hans";
    form2.setId(id2);
    interpreter.setDocument(document, null, configuration);
    final Dialog dialog1 = interpreter.getDialog(id1);
    Assert.assertEquals(id1, dialog1.getId());
    final Dialog dialog2 = interpreter.getDialog(id2);
    Assert.assertEquals(id2, dialog2.getId());
    final Dialog dialog3 = interpreter.getDialog("unknown");
    Assert.assertNull("execpted to find no form", dialog3);
    final Dialog dialog4 = interpreter.getDialog(null);
    Assert.assertNull("execpted to find no form", dialog4);
}