Question

I want to store whether something should be a String or an Integer in the database. My fantasy would be something like this:

Class FantasyClass{
  String someInfo
  Class whichClass
}

And then I could call it like this:

def thisThing = new FantasyClass(someInfo:'lalala',whichClass:String)

Is there any workaround to achieve this functionality?

Where I could go like:

def getAThing = FantasyClass.get(1)
assert getAThing.whichClass == String
assert 'thisIsAString' instanceof getAThing.whichClass  //THIS IS WHAT I REALLLLLLY WANT!!!

Answer 1

You can use the asType method

def getAThing = FantasyClass.get(1)
assert getAThing.whichClass == String
assert 'thisIsAString'.getClass() == getAThing.someInfo.asType(getAThing.whichClass)

Here’s a more generic example:

def value = 123
def otherThing = new FantasyClass(
   someInfo: value.toString(),
   whichClass: value.getClass()).save()

assert otherThing.someInfo.asType(getAThing.whichClass) instanceof Integer

And you can add a helper method to the domain class that will convert the String to the specified type for you:

def getTypedValue() {
   someInfo?.asType(foo)
}

and then you can do this:

assert otherThing.typedValue == 123