@Override
	public void write(EvaluationContext context, Object target, String name, Object newValue) throws AccessException {
		super.write(context, target, name, newValue);
	}
A {@link PropertyAccessor} reading values from a backing {@link Message} used by a
partition key. In a way this is similar than {@link MapAccessor} for header but also
adds 'payload' and 'headers' to be resolved. Having 'payload' or 'headers' keywords
in headers is not possible to access via this accessor.

@author Janne Valkealahti
spring-xd-hadoop/src/main/java/org/springframework/xd/integration/hadoop/expression/MessagePartitionKeyPropertyAccessor.java