learning scala pattern matching 02

code 

package com.aura.scala.day01

object patternMatching02 {

  def main(args: Array[String]): Unit = {
    def showNotifacation(notification: Notification):String = {
      notification match {
        case Email(sender, title, _) => s"You got an email from $sender with title : $title"
        case SMS(number, message) => s"You got an SMS from $number! Message:$message"
        case VoiceRecording(name, link) => s"you received a Voice Recording from $name! Click the link to hear it: $link"
        case _ =>  "other"
      }
    }
    val someSms = SMS("12345", "Are you there?")
    val someVoiceRecording = VoiceRecording("Tom", "voicerecording.org/id/123")
    println(showNotifacation(someSms))
    println(showNotifacation(someVoiceRecording))
  }
}

abstract class Notification
case class Email(sender: String,title: String, body: String) extends  Notification
case class SMS(caller: String, message: String) extends Notification
case class VoiceRecording(contactName: String, link: String) extends  Notification

resule :

"D:\Program Files\Java\jdk1.8.0_201\bin\java.exe" "-javaagent:D:\Program Files\JetBrains\IntelliJ IDEA 2019.1.3\lib\idea_rt.jar=5964:D:\Program Files\JetBrains\IntelliJ IDEA 2019.1.3\bin" -Dfile.encoding=UTF-8 -classpath "D:\Program Files\Java\jdk1.8.0_201\jre\lib\charsets.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\deploy.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\access-bridge-64.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\cldrdata.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\dnsns.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\jaccess.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\jfxrt.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\localedata.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\nashorn.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunec.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunjce_provider.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunmscapi.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunpkcs11.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\zipfs.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\javaws.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\jce.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\jfr.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\jfxswt.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\jsse.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\management-agent.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\plugin.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\resources.jar;D:\Program Files\Java\jdk1.8.0_201\jre\lib\rt.jar;C:\Users\admin\IdeaProjects\ScalaDay\out\production\ScalaDay;C:\Program Files (x86)\scala\lib\scala-actors-2.11.0.jar;C:\Program Files (x86)\scala\lib\scala-actors-migration_2.11-1.1.0.jar;C:\Program Files (x86)\scala\lib\scala-library.jar;C:\Program Files (x86)\scala\lib\scala-parser-combinators_2.11-1.0.4.jar;C:\Program Files (x86)\scala\lib\scala-reflect.jar;C:\Program Files (x86)\scala\lib\scala-swing_2.11-1.0.2.jar;C:\Program Files (x86)\scala\lib\scala-xml_2.11-1.0.4.jar" com.aura.scala.day01.patternMatching02
You got an SMS from 12345! Message:Are you there?
you received a Voice Recording from Tom! Click the link to hear it: voicerecording.org/id/123

Process finished with exit code 0

scala 模式匹配也可以在模式后面加上if　＜booleaｎ　ｅｘｐｒｅｓｓｉｏｎ＞　实现模式守卫。