Streamsx.topology project just released a new beta 0.8.0 release. ¬†This release introduces support for Scala applications.
For more information about Scala support, see this documentation: ¬†Scala Support.
Here’s a link to the new release: ¬†https://github.com/IBMStreams/streamsx.topology/releases/tag/v0.8.0_beta
For more information on how to write a Streams application using the Java Application API, check out this article: ¬†Java Application API – An Introduction