I am looking for use cases in which Apache Spark will work, and situations in which Spring XD threads are best suited.
Is there a technology overlap here? Does anyone face a situation where both are used?
Spring XD works great when you do not want to do any encodings and work with streams included in RabbitMQ, Gemfire, JDBC, HDFS, Redis, MongoDB.
Spring XD provides integration with the Spark stream to get the best of both. You can refer to the documentation here