/** Test of toJson method, of class PdfWord. */
 @Test
 public void testToJson() {
   assertTrue(instance.toJson() instanceof JSONObject);
   String expectedJson =
       "{\"layout\":[{\"width\":4.0,\"x\":0.0,\"y\":1.1,\"height\":1.1}],\"word\":{\"readable\":\"a\",\"normalised\":\"a\"}}";
   StringWriter out = new StringWriter();
   try {
     instance.toJson().writeJSONString(out);
     assertEquals(out.toString(), expectedJson);
   } catch (IOException ex) {
     fail("JSON data mismatch");
   }
 }