scala模式匹配与异常处理

1、与java switch类似

package com.cslc.day3

import scala.util.Random

object MatchApp {
  def main(args: Array[String]): Unit = {
    val names=Array("liu","wang","li")
    val name=names(Random.nextInt(names.length))
    name match {
      case "liu" => {println("刘老师")}
      case "wang" => {println("王老师")}
      case "li" => {println("李老师")}
      case _=>{println("没有老师")}

    }
  }
}

2、数组模式匹配

package com.cslc.day3



object MatchApp {
  def main(args: Array[String]): Unit = {
    greeting(Array("zhangsan"))
    greeting(Array("xiaoming","xiaohua"))
    greeting(Array("xx","ccc","xxx"))
    greeting(Array("zhangsan","xx","ccc","xxx"))
  }
  def greeting(arr:Array[String]): Unit = {
    arr match {
      case Array("zhangsan") => {println("this is zhangsan")}
      case Array(x, y) => {println("hi " + x + " and " + y)}
      case Array("zhangsan", _*) => {println("zhansan and his friends")}
      case _ => {
        println("every body")
      }
    }
  }

}

3、列表的模式匹配

package com.cslc.day3



object MatchApp {
  def main(args: Array[String]): Unit = {
    greeting(List("zhangsan"))
    greeting(List("lisi","wangwu"))
    greeting(List("zhangsan","lisi","xxx"))
    greeting(List("lisi","zhangsan","zhaopliu"))
  }
  def greeting(l:List[String]):Unit={
    l match{
      case  "zhangsan"::Nil =>{println("this is zhangsan ")}
      case x::y::z::Nil=>{println("hell "+x+" and "+y)}
      case "zhangsan"::tail=>{println("zhangsan and his friends")}
      case _ => {println("hello every body")}
    }
  }

}

 4、类型的模式匹配

package com.cslc.day3

import scala.collection.mutable.ListBuffer


object MatchApp {
  def main(args: Array[String]): Unit = {
    matchup("1")
    matchup(1)
    matchup(Map("xxx"->"xxxs"))
    matchup(obj=List("xxx"))
  }
  def matchup(obj:Any): Unit ={
    obj match{
      case x:Int=>{println("Int: "+x)}
      case x:String=>{println("String" +x)}
      case x:Map[_,_] =>{x.foreach(println)}
      case _ => {println("other type")}

    }
  }

}

5、异常处理

package com.cslc.day3

import scala.collection.mutable.ListBuffer


object MatchApp {
  def main(args: Array[String]): Unit = {
    try{
      val i=10/0
      println(i)
    }catch
      {
        case e:ArithmeticException =>{println(e.getCause+e.getMessage)}
        case e:Exception =>{println("error")}
      }finally {
      println("xxx")
    }
  }


}

6、case class模式匹配

package com.cslc.day3

import scala.collection.mutable.ListBuffer


object MatchApp {
  def caseclassMatch(person: Person): Unit ={
    person match{
      case CTO(name,floor)=>{println(name +"is working at "+floor)}
      case Empolyee(name)=>{println(name +"working  at all floor")}
      case Other(name)=>{println(name +" is only enter one floor")}
    }
  }

  def main(args: Array[String]): Unit = {
    caseclassMatch(CTO("bioamin",15))
    caseclassMatch(Empolyee("wuye"))
    caseclassMatch(Empolyee("penglong"))
  }
}
class Person
case class CTO(name:String,floor: Int) extends  Person
case class Empolyee(name:String) extends  Person
case class Other(name:String) extends  Person