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javaclojurejava-stream

How to use java.util.stream.Stream in Clojure?

(import java.nio.file.Files)
(import java.nio.file.Paths)
(import java.util.stream.Stream)

(def path 
  (Paths/get "." 
    (into-array ["data" "10000000.test.log"])))

(def stream 
  (Files/lines path))

This way I have:

stream
#object[java.util.stream.ReferencePipeline$Head 0x50129b8f
"java.util.stream.ReferencePipeline$Head@50129b8f"]

Is there a way to iterate over this without running out of memory? The suggestion on SO are not really helpful. The files is ~1G.

Solution

  • I wanted to iterate over the stream Java / imperative style to avoid blowing up the heap. I do not need to reduce on the stream, I need to process every line and take out one field and send it out. I think for this I probably better off with doseq.

    (doseq 
  [l (iterator-seq (.iterator stream))] 
    (println l))