EnumMap vs Properties

Question

Does anyone have thoughts on what's superior, EnumMap or Properties (or at least in my situation?) I am using a 3rd party software package that communicates between my code and their application using their method like so:

TheirRuntime.getInstance().getParameter(String paramName)

Currently I have created an enum that works like this:

public enum MyEnum {
    FOO_BAR ("fooBar"), BAZ_QUUX ("bazQuux");

    private final String varName;
    private MyEnum(String varName) {
        this.varName = varName();
    }
    public String varName() {
        return varName();
    }
}

Then I store the values in an EnumMap<MyEnum, Double>, which gets updated when the user changes something. My architecture is slightly more complicated than this but I'm omitting some details for the sake of SSCCE. Though I will mention that I load the values with something like:

for (MyEnum me : MyEnum.values()) {
     TheirRuntime.getInstance().getParameter(me.varName());
}

What I'm wondering is, would it make more sense to use Properties? This question has come up because I'm trying to build a test framework that doesn't involve the 3rd party software at all, and I'm trying to figure a good, easy way to load the parameters that doesn't use any 3rd party API calls, and a Properties file seems an easy way to go, which makes me wonder if I should just use Properties in the main class.

Thoughts?

Answer 1

Benefits of Enum are clear:
It provides you enum literals. You can use them to catch "wrong key" issues at compilation level.
Properties allow you flexibility - for example - you can read them from a file.
The big question is - how sure are you that the set of literals provided by the enum is fixed, and will not change?
For example, our system has a set of enum values, and since we're an open source project, we would like to build a plugin on top of it that theoretically should have used the enum values,
But plugin writers will not be able to use the original enum, as it has a fix set of literals, so either we modify our enum to a properties object, and let plugin writers register their "literals",
or we have to provide a supplementary system to our enum.
I'm sorry that I don't have a "clear cut" solution here.

Answer 2

The main difference between use of EnumMap and plain Properties (which is also a Map under the hood) is that the former will enforce allowed values of the keys that could be stored in given map, while Properties will allow to use any strings for those keys.