Load a key value file to a map in scala then load the values to a vector

1
votes

New to scala. I have a key value file containing

    key1=value1~value2 
    key2=value3~value4~value5
    key3=value7~value8

I want to load it to a map from a file. I want to find and match if I receive key1 or key2 at run time. Then store the corresponding values (separated by ~) to a vector. So that I can do foreach on the vector and perform different things based on the value.

2
arraysscalavector
What do you by a vector? Should line 2 be List("", "", "value3", "value4", "value5") or List("value3", "value4", "value5")? Could you provide as well what you've already tried? – Xavier Guihot
Please post what the resulting Vector should look like (i.e. its contents) along with whatever code you've tried so far. – jwvh
This is how I dealt with the situation val readFile = scala.io.Source.fromFile(Path+"/test.txt").getLines.map(line => { val tokens = line.split("""\=+""") // Use a regex to avoid empty tokens. Splitting file to 2 column and then a list (tokens(0), tokens(1)) }).toList val matchKey = readMapingFile.filter(_._1==Keys.trim()) val pickMatchedKV = matchKey(0) // I don't have duplicate keys in my case val value = pickMatchedKV._2 val spiltValuestoArray = value.split("~") spiltValuestoArray.foreach(println) passed keys via Keys – Sat

2 Answers

1
votes

Here is the solution, though it might not be the ideal solution, though it will give you the desired output:

Read lines from the file

val list = Source.fromFile("path").getLines().toList

then do the following:

  val outPutList = list.map { data =>
 val splittedList =  data.split("=").toList
  val listOfTupple =(splittedList.head,splittedList.tail.mkString.split("~").toList)
  listOfTupple
}

outPutList.toMap

Expected Output:

 Map(key1 -> List(value1, value2), key2 -> List(value3, value4,value5))

Iterate over the values to perform the desired action.

1
votes

Let's assume you have file test.txt which contains:

key1=value1~value2 
key2=value3~value4~value5
key3=value7~value8

Below code will parse and create List of Tuple with key and related to it List (it could be easily convert to Map -> just invoke toMap):

val filename = "test.txt"

val result = Source.fromFile(filename).getLines
  .map(line => {
    line.split("=") match {
      case Array(a, b) => (a, b.split("~").toList)
    }
  }).toList

println(result)

The result would be:

List((key1,List(value1, value2)), (key2,List(value3, value4, value5)), (key3,List(value7, value8)))

If you want Map you need just invoke toMap: println(result.toMap) Result for that would be:

Map(key1 -> List(value1, value2), key2 -> List(value3, value4, value5), key3 -> List(value7, value8))