scala，讀取JSON字串并從JSON陣列回傳特定??值

我有一個 JSON 字串，其中包含以下文本：

[   {"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"}
]

我想檢索 id 等于特定值的行的值，例如，如果我正在尋找 id="offent"，則回傳的值應該是“oui”。

我是 scala 的新手，我正在尋找一個可以在不使用本機 java 代碼的情況下輕松實作這一目標的庫。

uj5u.com熱心網友回復：

你可以使用值得信賴的org.json，

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

而不是在代碼中：

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)

uj5u.com熱心網友回復：

為了方便地在 Scala 中使用 JSON，您可以使用第戎庫。

1. 將依賴項添加到您的build.sbt：

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

2. 通過添加 import 子句打開對動態型別的支持：

import scala.language.dynamics._

或通過設定 scala 編譯器選項：

scalacOptions  = "-language:dynamics"

3. dijon為主要功能添加包物件的匯入：

import dijon._

4. 使用以下代碼決議、查找和列印值：

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 })

5. （可選）匯入jsoniter-scala-core擴展功能的包物件，例如掃描 JSON 陣列java.io.InputStream并處理決議的值，而不將所有這些值保存在記憶體中：

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
}

標籤：json 斯卡拉

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