Scala example source code file (getClassTest.scala)

This example Scala source code file (getClassTest.scala) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Scala tags/keywords

a, a, anyrefs, anyvals, array, b, b, manifest, moreanyrefs, moreanyrefs, test, test, unit

The Scala getClassTest.scala source code

class AnyVals {
  def f1 = (5: Any).getClass
  def f2 = (5: AnyVal).getClass
  def f3 = 5.getClass
  def f4 = (5: java.lang.Integer).getClass
  def f5 = (5.asInstanceOf[AnyRef]).getClass
  
  // scalap says:
  //
  // def f1 : java.lang.Class[?0] forSome {type ?0} = { /* compiled code */ }
  // def f2 : java.lang.Class[?0] forSome {type ?0} = { /* compiled code */ }
  // def f3 : java.lang.Class[scala.Int] = { /* compiled code */ }
  // def f4 : java.lang.Class[?0] forSome {type ?0 <: java.lang.Integer} = { /* compiled code */ }
  // def f5 : java.lang.Class[?0] forSome {type ?0 <: scala.AnyRef} = { /* compiled code */ }
  //
  // java generic signature says:
  //
  // f1: java.lang.Class<?>
  // f2: java.lang.Class<?>
  // f3: java.lang.Class<java.lang.Object>
  // f4: java.lang.Class<? extends java.lang.Integer>
  // f5: java.lang.Class<?>  
}

class AnyRefs {
  class A
  class B extends A
  
  def f1 = (new B: Any).getClass().newInstance()
  def f2 = (new B: AnyRef).getClass().newInstance()
  def f3 = (new B: A).getClass().newInstance()
  def f4 = (new B: B).getClass().newInstance()
  
  def f0[T >: B] = (new B: T).getClass().newInstance()

  def f5 = f0[Any]
  def f6 = f0[AnyRef]
  def f7 = f0[A]
  def f8 = f0[B]
}

class MoreAnyRefs {
  trait A
  trait B

  // don't leak anon/refinements
  def f1 = (new A with B { }).getClass()
  def f2 = (new B with A { }).getClass()
  def f3 = (new { def bippy() = 5 }).getClass()
  def f4 = (new A { def bippy() = 5 }).getClass()
}

object Test {
  def returnTypes[T: Manifest] = (
    manifest[T].erasure.getMethods.toList 
      filter (_.getName startsWith "f")
      sortBy (_.getName)
      map (m => m.getName + ": " + m.getGenericReturnType.toString)
  )

  def main(args: Array[String]): Unit = {
    returnTypes[AnyVals] foreach println
    returnTypes[AnyRefs] foreach println
    returnTypes[MoreAnyRefs] foreach println
  }
}