How do I call a Scala Object method using reflection?

Question

say, I have the following:

trait SomeTrait {
  def someMethod: String;
}

object SomeObject extends SomeTrait {
  def someMethod = \"something\";
}
         


        

Answer 1

For classes, this can be done pretty easily using the standard java reflection classOf method. For Scala objects, it is a bit more work, but it still can be done:

trait SomeTrait { def someMethod: String}
object SomeObject extends SomeTrait { def someMethod = "something"}

class SomeClass extends SomeTrait { def someMethod = "something"}

object Main {
 def main(args:Array[String]) = {
    val someClassTrait:SomeTrait = Class.forName("SomeClass").newInstance().asInstanceOf[SomeTrait]
    println("calling someClassTrait: " + someClassTrait.someMethod)
    val objectName = "SomeObject$"
    val cons = Class.forName(objectName).getDeclaredConstructors(); 
    cons(0).setAccessible(true);
    val someObjectTrait:SomeTrait = cons(0).newInstance().asInstanceOf[SomeTrait]
    println("calling someObjectTrait: " + someObjectTrait.someMethod)
  }
}

//prints:
calling someClassTrait: something
calling someObjectTrait: something