### Question:
String extends Message { public java.lang.String getData() { return this.data; } String();  String(java.lang.String data); java.lang.String getData(); @Override String clone(); static String fromJsonString(java.lang.String jsonString); static String fromMessage(Message m); static String fromJsonObject(JsonObject jsonObject); static final java.lang.String FIELD_DATA; static final java.lang.String TYPE; }### Answer:
@Test public void testConstructor() { assertEquals("", empty.getData()); assertEquals("{\"data\":\"\"}", empty.toString()); assertEquals(1, empty.toJsonObject().size()); assertEquals("", empty.toJsonObject().getString(String.FIELD_DATA)); assertEquals(String.TYPE, empty.getMessageType()); }
@Test public void testStringConstructor() { assertEquals("test", s1.getData()); assertEquals("{\"data\":\"test\"}", s1.toString()); assertEquals(1, s1.toJsonObject().size()); assertEquals("test", s1.toJsonObject().getString(String.FIELD_DATA)); assertEquals(String.TYPE, s1.getMessageType()); }