df.show() Not printing to file

Question

I have a log of the steps of my application, and would like to print the result of "df.show(5)" to a file as a sample of the data that is received by the process.

I found this solution, which allows me to store the result of "show" into a String. The String prints nicelly into the console, but when I try to write it to a file all I get is a blank Line.

This is where I am directing that String to write the file, but no errors are given, and the resulting line on file is blank:

def writeLineOnFile(input: String, path: String): Unit = {
    val file = new File(path)
    val fw = new FileWriter(file, true)
    try {
      fw.write( input)
    }
    finally fw.close()
  }

Piece of code used to try to transform the output from df.show into a printable string, but comes out empty in the file:

def getOutAsString(input: Unit): String ={
    val oldPs = Console.out
    val baos = new ByteArrayOutputStream()
    val ps =  new java.io.PrintStream(baos);
    Console.withOut(ps) {
      input
    }
    new String(baos.toByteArray)
  }

yes, it writes strings, but the problem seems to be related tot he linked solution, where the string resulting from "df.show" seems to be empty — Welsige, Dec 16 '19 at 13:32

score 0 · Answer 1 · answered Dec 12 '19 at 14:16

0

maybe try this:

  /**
     * write a `String` to the `path`.
     */
    def writeLineOnFile(input: String, path: String): Unit = {
        val file = new File(path)
        val bw = new BufferedWriter(new FileWriter(file))
        bw.write(input)
        bw.close()
    }

answered Dec 12 '19 at 14:16

amer

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Seems my problem is that Console.withOut is not producing a String that can be saved, my resulting string is empty – Welsige Dec 16 '19 at 13:38
Did you fix it ? – amer Dec 16 '19 at 13:58
No, last try I did the string coming ou from withOut function remains empty – Welsige Dec 16 '19 at 14:12

df.show() Not printing to file

1 Answers1