09.scala操作外部数据

读取文件和网络数据

一行一行读

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一个字母一个字母读

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通过网络读

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读取mysql

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读取xml文件

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读取XML属性内容

import scala.xml.XML

object XMLApp {
  def main(args: Array[String]): Unit = {
    //    loadXML()
    readXMLAttr()
  }


  def readXMLAttr() = {
    val xml = XML.load(this.getClass.getClassLoader.getResource("xxj.xml"))
    //打印一下结构
    println(xml)
    //header/field  header下的field
    val headerField = xml \ "header" \ "field"
    println(headerField)
    //all field所有的field
    val fields = xml \\ "field"
    for (field <- fields) {
      println(field)
    }
    //header/field/name header下field下name的值
    val fieldAttributes = (xml \ "header" \ "field").map(_ \ "@name")
    val fieldAttributes = (xml \ "header" \ "field" \\ "@name")
    for (fieldAttribute <- fieldAttributes) {
      println(fieldAttribute)
    }
    //name=hahahaha的message标签
    val filters = (xml \\ "message")
      .filter(_.attribute("name")
        .exists(_.text.equals("hahahaha")))
    val filters = (xml \\ "message")
      .filter(x => ((x \ "@name").text)
        .equals("hahahaha"))
    for (filter <- filters) {
      println(filter)
    }
    //header/field/name content获取内容
    (xml \ "header" \ "field")
      .map(x => (x \ "@name", x.text, x \ "@required"))
      .foreach(println)
  }

  def loadXML(): Unit = {
    val xml1 = XML.load(this.getClass.getClassLoader.getResource("test.xml"))
    //    println(xml1)
    val xml2 = XML.load(new FileInputStream("C:\\workspaces\\workspack_scala_2\\src\\main\\resources\\test.xml"))
    //    println(xml2)
    val xml3 = XML.load(new FileInputStream("C:\\workspaces\\workspack_scala_2\\src\\main\\resources\\test.xml"))
    //    println(xml3)
  }

}

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