@Override
	public String toString() {
		StringBuilder s = new StringBuilder();
		s.append("Link[from=").append(from).append(",to=").append(to);
		if (properties != null) {
			s.append(",properties=").append(properties);
		}
		s.append("]");
		return s.toString();
	}
Properties on a link can capture the name of a potential transition that
would lead to this link being taken when the 'from' job completes.
spring-xd-dirt/src/main/java/org/springframework/xd/dirt/job/dsl/Link.java