If you use Scala 2.10 reflection, this answer is half of the things you need. It will give you the method symbols of the case class, so you know the order and names of arguments:
import scala.reflect.runtime.{universe => ru}
import ru._
def getCaseMethods[T: TypeTag] = typeOf[T].members.collect {
case m: MethodSymbol if m.isCaseAccessor => m
}.toList
case class Person(name: String, age: Int)
getCaseMethods[Person] // -> List(value age, value name)
You can call .name.toString
on these methods to get the corresponding method names.
The next step is to invoke these methods on a given instance. You need a runtime mirror for that
val rm = runtimeMirror(getClass.getClassLoader)
Then you can "mirror" an actual instance:
val p = Person("foo", 33)
val pr = rm.reflect(p)
Then you can reflect on pr
each method using reflectMethod
and execute it via apply
. Without going through each step separately, here is a solution altogether (see the val value =
line for the mechanism of extracting a parameter's value):
def caseMap[T: TypeTag: reflect.ClassTag](instance: T): List[(String, Any)] = {
val im = rm.reflect(instance)
typeOf[T].members.collect {
case m: MethodSymbol if m.isCaseAccessor =>
val name = m.name.toString
val value = im.reflectMethod(m).apply()
(name, value)
} (collection.breakOut)
}
caseMap(p) // -> List(age -> 33, name -> foo)