Scala 模式匹配的五种情形，值，case class ，optional ，数据类型，集合内数据

package com.xing.listfile

/**
  * Created by DengNi on 2017/2/11.
  */
class DataFramework

case class ComputationFramework(val name:String,val age:Int) extends DataFramework
case class StorageFramework(name:String ,age :Int) extends  DataFramework

object helloPatternMatch {

  def main(args: Array[String]) {

    //模式匹配对值匹配
    getSalary("spark")
    getSalary("spark1")
    getSalary("spark",12)
    getSalary("spark1",16)

    //模式匹配对数据类型的匹配
    getMatchType(12)
    getMatchType("Hi")
    getMatchType(12.00)
    getMatchType(Array(1,2))
    getMatchType(Array("string"))
    getMatchType(Seq(12))

    //模式匹配对集合内容的匹配
    getMatchCollection(Array("scala"))
    getMatchCollection(Array("spark"))
    getMatchCollection(Array("spark","scala"))
    getMatchCollection(Array("java","spakdg")) //匹配到java后 后面的将不会在进行匹配

    //模式匹配case class 匹配
    getMatchCaseClass(ComputationFramework("hi", 12))
    getMatchCaseClass(StorageFramework("hello",34))
    ///getMatchCaseClass(Array("string")) error can write another one that extends Data but not shows in the def function

    //模式匹配对optional 匹配
    getMatchOption("scala",Map("scala"-> "","spark"->"spark"))
    getMatchOption("java",Map("scala"-> "","spark"->"spark"))

  }
  //模式匹配对值匹配
  def getSalary(name:String): Unit ={
    name match {

        case "spark" => println("high");
        case "hadoop" => println("low")
        case _ => println("unknown")

    }
  }

  def getSalary(name:String,age:Int): Unit ={
    name match {

      case "spark" => println("high "+ age);
      case "hadoop" => println("low")
      case _ if age > 15 => println("maybe " + age)
      case _ if age <= 15 => println("unknown")

    }
  }

  //模式匹配对数据类型的匹配
  def getMatchType(msg:Any): Unit ={
    msg match {
        case i:Int => println("Integer")
        case d:Double =>println("Double")
        case s:String =>println("String")
        case a:Array[String] =>println("Array[String]")
        case a:Array[Int] =>println("Array[Int]")
        case _ => println("unknown type")

    }
  }

  //模式匹配对集合内容的匹配
  def getMatchCollection(msg :Array[String]): Unit ={
      msg match {
         case Array("scala") => println("1 element")
         case Array("spark","scala") => println("2 elements")
         case Array("java",_*) => println("many elements")
         case  _ => println("unknown")

      }

  }
  //模式匹配case class 匹配
  def getMatchCaseClass(data:DataFramework): Unit ={  //传入的是父类的数据类型 ，这也解释了什么要extends

    data match {

      case ComputationFramework(name,age) => println("this is using to computation") //name and age passed by mian()
      case StorageFramework(name,age) => println("this is for storage")
      case _ => println("unknown")

    }
  }
  //模式匹配对optional 匹配
  def getMatchOption(name :String,contents:Map[String,String]): Unit ={    //采用的是Map Key 查 vale 的 情形
    contents.get(name) match {
      case Some(values) => println("exists")
      case None => println("not exists")
    }

  }

}