@Test
 public void parseJson_single() {
   final VCardParameters params = new VCardParameters();
   JCardValue value = JCardValue.single("value");
   sensei
       .assertParseJson(value)
       .dataType(VCardDataType.TEXT)
       .params(params)
       .warnings(1)
       .run(
           new Check<TestProperty>() {
             public void check(TestProperty property) {
               assertEquals("value", property.value);
               assertSame(params, property.getParameters());
             }
           });
 }
 @Override
 protected JCardValue _writeJson(T property) {
   return JCardValue.single(write(property, VCardVersion.V4_0));
 }