private MappingJacksonValue getOrCreateContainer(Object body) {
		return body instanceof MappingJacksonValue ? (MappingJacksonValue) body :
				new MappingJacksonValue(body);
	}
Wrap the body in a {@link MappingJacksonValue} value container (for providing
additional serialization instructions) or simply cast it if already wrapped.
src/main/java/im/zhaojun/zfile/core/aspect/CommonResultControllerAdvice.java