@Override
	protected Class<?>[] supportedPayloadTypes() {
		return new Class<?>[] { Tuple.class };
	}
A {@link org.springframework.messaging.converter.MessageConverter}
to convert a {@link Tuple} to a JSON String

@author David Turanski
spring-xd-dirt/src/main/java/org/springframework/xd/dirt/integration/bus/converter/TupleToJsonMessageConverter.java