@AssertTrue(message = "explicit partitions can only be set when using single topic source")
	public boolean isPartitionsOptionValid() {
		return (Arrays.asList(topics.split("\\s*,\\s*")).size() > 1) ? !StringUtils.hasText(partitions) : true;
	}
Module options for Kafka source module.

@author Ilayaperumal Gopinathan
@author Marius Bogoevici
extensions/spring-xd-extension-kafka/src/main/java/org/springframework/integration/x/kafka/KafkaSourceModuleOptionsMetadata.java