Scala: How do I dynamically instantiate an object and invoke a method using reflection?

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There is an easier way to invoke method reflectively without resorting to calling Java reflection methods: use Structural Typing.

Just cast the object reference to a Structural Type which has the necessary method signature then call the method: no reflection necessary (of course, Scala is doing reflection underneath but we don’t need to do it).

class Foo {
  def hello(name: String): String = "Hello there, %s".format(name)
}

object FooMain {

  def main(args: Array[String]) {
    val foo  = Class.forName("Foo").newInstance.asInstanceOf[{ def hello(name: String): String }]
    println(foo.hello("Walter")) // prints "Hello there, Walter"
  }
}

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