CODEWITHSUNDEEP
androidfilekotlinhashmap
user11240805
user11240805

Reputation:

Read .txt and put information in the hashMap

I have a list of elements, the first element is a name city and second information is about thecity. I want read the file cities.txt and put the information of the list in the hashMap. In the file cities.txt the cities and the elements is separate for one tab. But when i put the pieces in the hashMap the second pieces isn't save.

private fun readFile() {
    var cityToDefn = java.util.HashMap<String, String>()
    val cities = ArrayList<String>()
    val reader = Scanner(resources.openRawResource(R.raw.cities))
    while (reader.hasNextLine()) {
        val line = reader.nextLine()
        var pieces = line.split("\\s".toRegex())

        if (pieces.size >= 2) {
            cities.add(pieces[0])
            cityToDefn.put(pieces[0], pieces[1])
        }
    }
}

cities.txt

 lisboa  castelo de são jorge
 porto   torre dos clerigos
 aveiro  ria
 lisboa  terreiro do paço
 porto   avenida dos aliados
 lisboa  marques de pombal
 aveiro  igreja da glória

Upvotes: 1

Views: 43

Answers (2)

Tenfour04
Tenfour04

Reputation: 93629

You say there's a tab after the cities, but in your example it looks like multiple spaces. So you can use \\s+ to split on the first group of white space. And add a limit of two, so the description is not broken up:

var pieces = line.split("\\s+".toRegex(), 2)

What if there are cities with two-word names? Then I think you really need a tab after the city name, and you could split on a tab character, without regex:

var pieces = line.split('\t')

Upvotes: 1

Neo
Neo

Reputation: 2039

Try to use Kotlin's classes when you operate with Kotlin.

This would solve the problem:

private fun readFile() {
    val cityToDefn = mutableMapOf<String,String>()
    val reader = Scanner(resources.openRawResource(R.raw.cities))
    while (reader.hasNextLine()) {
        val line = reader.nextLine()

        val left = msg.substringBefore(' ')
        val right = msg.substringAfter(' ')

        cityToDefn[left] = right
    }
    val cities = cityToDefn.keys
}

BTW: The right String will sometimes have some spaces in front, so you maybe want to filter them out.

Upvotes: 0

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