Question

File lstFile = new File(lstFileName).withWriter{out->
            archivedFiles.each {out.println it.name}
}

archivedFiles is a List objects .. I am getting an error that says:

Cannot cast object with class 'java.util.ArrayList' to class 'java.io.File'.

I am only interested in writing out file names contained in the list to the NEWLY created file

Answer 1

That’s beacuse the withWriter block is returning the last thing in the block by default (which is the archivedFiles list)

To do what you’re trying to do, you’d need to do:

File lstFile = new File(lstFileName)
lstFile.withWriter{ out ->
  archivedFiles.each {out.println it.name}
}

or this should work too:

File lstFile = new File( lstFileName ).with { file ->
  file.withWriter{ out ->
    archivedFiles.each {out.println it.name}
  }
  file
}