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class Spark
trait Hadoop
object Flink //單例
class Java{
class Scala
}
object Type_Advanced {
def main(args: Array[String]) {
println(typeOf[Spark]) //結果：com.dt.scala.bestpractice.Spark
println(classOf[Spark]) //Class[_ <: Spark]，結果：class com.dt.scala.bestpractice.Spark
val spark = new Spark
println(spark.getClass); //結果：class com.dt.scala.bestpractice.Spark
println(classOf[Hadoop]) //結果：interface com.dt.scala.bestpractice.Hadoop
println(typeOf[Hadoop]) //結果：com.dt.scala.bestpractice.Hadoop
println(Flink.getClass) //結果：class com.dt.scala.bestpractice.Flink$，這個$說明，在Scala中，object背後也是有類的
// println(classOf[Flink])
val java1 = new Java
val java2 = new Java
val scala1 = new java1.Scala
val scala2 = new java2.Scala
println(scala1.getClass) //結果：class com.dt.scala.bestpractice.Java$Scala
println(scala2.getClass) //結果：class com.dt.scala.bestpractice.Java$Scala
println(typeOf[java1.Scala] == typeOf[java2.Scala]) //false
println(typeOf[java1.Scala]) //結果：java1.Scala
println(typeOf[java2.Scala]) //結果：java2.Scala
//type是更詳細的資訊，而class是更抽象的資訊
println(classOf[List[Int]] == classOf[List[String]]) //true
println(typeOf[List[Int]] == typeOf[List[String]]) //false
println(classOf[List[Int]]) //class scala.collection.immutable.List
println(classOf[List[String]]) //class scala.collection.immutable.List
println(typeOf[List[Int]]) //scala.List[Int]
println(typeOf[List[String]]) //scala.List[String]
}
}

Type與Class

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