beam.clj

(let [p (Pipeline/create (PipelineOptionsFactory/create))]
  (doto
   (.. p
       (apply TextIO.Read/from ("..."))
       (apply "ExtractWords"
              (ParDo/of (reify DoFn
                          (processElement [this context]
                            ...
                            ))))
       (apply (Count/perElement))
       (apply "FormatResults"
              (MapElements/via (reify SimpleFuntion
                                 (apply [this input]
                                   ...))))
       (apply (TextIO.Write/to "wordcounts")))
    (.. run waitUntilFinish)))

Quick translation of this: https://github.com/apache/beam/blob/master/examples/java/src/main/java/org/apache/beam/examples/MinimalWordCount.java