gistfile1.java

@JsonTypeInfo(use=JsonTypeInfo.Id.CLASS)
	public static class Wrapper {

	}
	
	@Test
	public void testPolymorphicTypeIsReturnedWithoutMap() throws Exception {
		Wrapper alertNotifyTag = new Wrapper();

		String serialized = mapper.writeValueAsString(alertNotifyTag);
		System.out.println(serialized);
		assertTrue(serialized.contains("@class"));
	}

	@Test
	public void testTypeIsReturnedWithMap() throws Exception {
		Wrapper alertNotifyTag = new Wrapper();

		Map<String, Wrapper> map = ImmutableMap.of("something", alertNotifyTag);
		String serialized = mapper.writeValueAsString(map);
		System.out.println(serialized);
		assertTrue(serialized.contains("@class")); // disappears
	}