scala, read JSON string and return a specific value from the JSON array-CodePudding

I have a JSON string that contains the text bellow:

[   {"origin": "24u","name": "","id": "itcobtpbtc","value": "n"},
    {"origin": "24u","name": "","id": "offent","value": "oui"},
    {"origin": "24u","name": "","id": "network","value": "btip"},
    {"origin": "24u","name": "","id": "modpbx","value": "vide"},
    {"origin": "24u","name": "","id": "egtplg","value": "1"},
    {"origin": "24u","name": "","id": "zipbxcent","value": "non"},
    {"origin": "24u","name": "","id": "typpbx","value": "pabx"},
    {"origin": "24u","name": "","id": "egttyp","value": "gtr"},
    {"origin": "24u","name": "","id": "egtval","value": "240"},
    {"origin": "24u","name": "","id": "egtunt","value": "mn"},
    {"origin": "24u","name": "","id": "codec","value": "g71120ms"},
    {"origin": "24u","name": "","id": "modifseqsda","value": "non"},
    {"origin": "24u","name": "","id": "infra_mode_ha_site","value": "non"},
    {"origin": "24u","name": "","id": "numndi","value": "0238300385"},
    {"origin": "24u","name": "","id": "nbcanout","value": "0"},
    {"origin": "24u","name": "","id": "dbdrtc","value": "non"},
    {"origin": "24u","name": "","id": "egtcod","value": "s2"},
    {"origin": "24u","name": "","id": "numprtclp","value": "0044lfv4"},
    {"origin": "24u","name": "","id": "egtlib","value": "gtr 4h s2 lundi au samedi 8h a 18h "},
    {"origin": "24u","name": "","id": "dpmcible","value": "salto"},
    {"origin": "24u","name": "","id": "nbcanin","value": "0"},
    {"origin": "24u","name": "","id": "nbcan","value": "4"},
    {"origin": "24u","name": "","id": "nomsit","value": "foyer hebergement"},
    {"origin": "24u","name": "","id": "integrateur","value": "orange"}
]

I want to retrieve the value of a row where id equals a specific value, for example if I'm looking for the id="offent", the returned value should be "oui".

I'm new to scala and I'm looking for a library that could make that easy without using native java code.

CodePudding user response：

You can use trustworthy org.json,

    <dependency>
        <groupId>org.json</groupId>
        <artifactId>json</artifactId>
        <version>latest</version>
    </dependency>

And than in the code:

val json =
  """
    |[   {"origin": "24u","name": "","id": "itcobtpbtc","value": "n"},
    |    {"origin": "24u","name": "","id": "offent","value": "oui"},
    |    {"origin": "24u","name": "","id": "network","value": "btip"},
    |    {"origin": "24u","name": "","id": "modpbx","value": "vide"},
    |    {"origin": "24u","name": "","id": "egtplg","value": "1"},
    |    {"origin": "24u","name": "","id": "zipbxcent","value": "non"},
    |    {"origin": "24u","name": "","id": "typpbx","value": "pabx"},
    |    {"origin": "24u","name": "","id": "egttyp","value": "gtr"},
    |    {"origin": "24u","name": "","id": "egtval","value": "240"},
    |    {"origin": "24u","name": "","id": "egtunt","value": "mn"},
    |    {"origin": "24u","name": "","id": "codec","value": "g71120ms"},
    |    {"origin": "24u","name": "","id": "modifseqsda","value": "non"},
    |    {"origin": "24u","name": "","id": "infra_mode_ha_site","value": "non"},
    |    {"origin": "24u","name": "","id": "numndi","value": "0238300385"},
    |    {"origin": "24u","name": "","id": "nbcanout","value": "0"},
    |    {"origin": "24u","name": "","id": "dbdrtc","value": "non"},
    |    {"origin": "24u","name": "","id": "egtcod","value": "s2"},
    |    {"origin": "24u","name": "","id": "numprtclp","value": "0044lfv4"},
    |    {"origin": "24u","name": "","id": "egtlib","value": "gtr 4h s2 lundi au samedi 8h a 18h "},
    |    {"origin": "24u","name": "","id": "dpmcible","value": "salto"},
    |    {"origin": "24u","name": "","id": "nbcanin","value": "0"},
    |    {"origin": "24u","name": "","id": "nbcan","value": "4"},
    |    {"origin": "24u","name": "","id": "nomsit","value": "foyer hebergement"},
    |    {"origin": "24u","name": "","id": "integrateur","value": "orange"}
    |]""".stripMargin

case class YourModel(origin:String, name:String,id:String, value:String)

import collection.JavaConversions._
val jsonArray: JSONArray = new JSONArray(json)
val yourMap = jsonArray.toSeq.map(x=>{
  val jsonObject = new JSONObject(x.toString)
  YourModel(
    jsonObject.get("origin").toString,
    jsonObject.get("name").toString,
    jsonObject.get("id").toString,
    jsonObject.get("value").toString)
}).map(x=>x.id -> x).toMap

println(yourMap.get("offent").get.value)

CodePudding user response：

For handy working with JSON in Scala you can use dijon library.

Add dependency to your build.sbt:

libraryDependency  = "me.vican.jorge" %% "dijon" % "0.6.0" // Use %%% instead of %% for Scala.js

Turn on support of dynamic types by adding import clause:

import scala.language.dynamics._

or by setting the scala compiler option:

scalacOptions  = "-language:dynamics"

Add import of the package object of dijon for the main functionality:

import dijon._

Use following code to parse, find and print the value:

val str =
  """[
    |    {"origin": "24u","name": "","id": "itcobtpbtc","value": "n"},
    |    {"origin": "24u","name": "","id": "offent","value": "oui"},
    |    {"origin": "24u","name": "","id": "network","value": "btip"},
    |    {"origin": "24u","name": "","id": "modpbx","value": "vide"},
    |    {"origin": "24u","name": "","id": "egtplg","value": "1"},
    |    {"origin": "24u","name": "","id": "zipbxcent","value": "non"},
    |    {"origin": "24u","name": "","id": "typpbx","value": "pabx"},
    |    {"origin": "24u","name": "","id": "egttyp","value": "gtr"},
    |    {"origin": "24u","name": "","id": "egtval","value": "240"},
    |    {"origin": "24u","name": "","id": "egtunt","value": "mn"},
    |    {"origin": "24u","name": "","id": "codec","value": "g71120ms"},
    |    {"origin": "24u","name": "","id": "modifseqsda","value": "non"},
    |    {"origin": "24u","name": "","id": "infra_mode_ha_site","value": "non"},
    |    {"origin": "24u","name": "","id": "numndi","value": "0238300385"},
    |    {"origin": "24u","name": "","id": "nbcanout","value": "0"},
    |    {"origin": "24u","name": "","id": "dbdrtc","value": "non"},
    |    {"origin": "24u","name": "","id": "egtcod","value": "s2"},
    |    {"origin": "24u","name": "","id": "numprtclp","value": "0044lfv4"},
    |    {"origin": "24u","name": "","id": "egtlib","value": "gtr 4h s2 lundi au samedi 8h a 18h "},
    |    {"origin": "24u","name": "","id": "dpmcible","value": "salto"},
    |    {"origin": "24u","name": "","id": "nbcanin","value": "0"},
    |    {"origin": "24u","name": "","id": "nbcan","value": "4"},
    |    {"origin": "24u","name": "","id": "nomsit","value": "foyer hebergement"},
    |    {"origin": "24u","name": "","id": "integrateur","value": "orange"}
    |]""".stripMargin
val json = parse(str)
println(json.toSeq.collect { case x if x.id.asString.contains("offent") => x.value })

(Optionally) Import a package object of jsoniter-scala-core for extended functionality like scanning through JSON arrays from java.io.InputStream and handle parsed values without holding all of them in the memory:

import com.github.plokhotnyuk.jsoniter_scala.core._

val in: java.io.InputStream = new java.io.ByteArrayInputStream(str.getBytes)
scanJsonArrayFromStream[SomeJson](in) { x => 
  if (x.id.asString.contains("offent")) {
    println(x.value)
  }
  true
}