Reading a .bz2 file

Question
1

I have a directory full of files which have been compressed and now have a .cnf.bz2 extension. Of course I could uncompress each into in the file system into a .cnf file (e.g., into /tmp), before reading it into my scale program. However, is there a more streamline way. I.e., someway to open the file, and effectively read lines from the uncompressed file, without having to physically create the file on disk?

2

Search the web for “scala bz2”. If this comes up empty, search for “java bz2” instead. Likely first match: commons-compress. Search for “commons-compress maven”, add to your build.sbt:

libraryDependencies += "org.apache.commons" % "commons-compress" % "1.18"

The uncompress functionality is implemented via an InputStream adapter, so you can just throw it at a Source, for example:

import java.nio.file._
import org.apache.commons.compress.compressors.bzip2._
import resource._
import scala.io._
// ...
val bz2Path = Paths.get(bz2PathStr)
for(src <- managed(Source.fromInputStream(new BZip2CompressorInputStream(Files.newInputStream(bz2Path))))) {
  src.getLines.foreach(println)
}
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