Create a country with specific values from a pre-determined list

Question

Background

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I'm currently working on an Android application which asks the user a question. At the moment I'm creating the modules for asking the questions. Right now I'm working on a topography module, which will be able to ask the user all kinds of questions about a certain country that will be shown to them.

Problem

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For this module I will need a list of all the countries in the world. I currently have a Country class that has a String[] array that has all the countries English names in it (±200). I also want a few other properties in the Country class, such as their capitals, provinces and the translations for them. All of these properties should be selected from a predetermined list. This list should also be rather flexible, so that it in the future I can easily add new properties to them.

The problem I'm currently having is that I'm not quite sure how to create such a list. I've had a couple of ideas but all of them seem faulty, cumbersome or they just plain don't work in Java. Here is an example of a few of my ideas:

• Create a multidimensional array that holds all the countries values which can then be easily selected with predefined indices. This is something that I often use when programming in PHP, because it can hold all kinds of different types. You can also define the keys (indices) of the array in PHP, but this doesn't work in Java.
• Create an enum for all the countries and use the int associated with the specific country to select values from a capital/province array. This is a bit too cumbersome for my liking, it would require me to create an enormous array everytime I would want to add another property/question for the country (making a mess of the Country class in my opinion).
• Create classes for all the properties I want Country to have. This has the advantage that I could expand on these classes further with more information (such as giving a Capital class properties such as: amount_of_residents ), and has the advantage of perhaps creating a sophisticated translation class. I'm just wondering if this is the most efficient/logical way to proceed?

I feel that there should be some very nice solution for this problem I'm facing, but for the love of me I just can't figure it out. If you guys have any idea as what would be the best option (I'm currently leaning to option 3), or give me another solution to the problem that's more efficient, it would be greatly appreciated.

Note: I haven't added any code, because I didn't feel it would be necessary. If anyone would like to see some code I would be happy to provide it.

Answer 1

I believe you should go with the last approach, it should be something like the below sample code PS

    class Country {
    String countryName;
    String capital;
    int noOfResidents;
    List<String> provinces;

    //getter & setters for them

    public void setCountryName(String countryName)
    {
    this.countryName=countryName;
    }

    //And so on & forth
    }

    class SetCountryDetails {

    public static void main(String[] args){

    Map<String, Country> countryData = new HashMap<String, Country>();
    //Using a map facilitates easier fetch for the countries. You can just
    //provide the key of the country, for an instance to fetch the data for Germany 
    //just write countryData.get("Germany");

    Country countryOne = new Country();
    countryOne.setCountryName("Germany");
    countryData.put("Germany", countryOne);

    Country countryTwo = new Country();
    countryOne.setCountryName("India");
    countryData.put("India", countryTwo);

     }
    }

This approach enables you to add or delete a property to the Country class anytime without much hassle.

Answer 2

I'm not sure I totally understand what the issue really is. Basically you seem to have a domain object called Country that has a number of properties, and you seem to want to extend dynamically? Perhaps some code would help to solve your problem.

Answer 3

As per my understanding from your question, You need to use the list of Countries and respective properties of those Countries. And those properties need to be flexible in future to add/remove. For this you can maintain the list of countries and related properties in a property file or an XML file, which can be flexible in future to add/remove properties if required. If my understanding is wrong then make it clear for me. :)