@Test
 public void shouldProcessSimpleKeyword() throws Exception {
   testee.startScan("hallo");
   MethodProductionElement next = testee.next();
   assertThat(next.getCapturedString()).isEqualTo("hallo");
   assertThat(next.getProductionElementType()).isEqualTo(Keyword);
 }
 @Override
 public String get(MethodProductionElement mpe) {
   return mpe.getCapturedString();
 }