Factorium-J7

A simple generator and factory framework.

Compatibility

Compatibility is guaranteed for Java 7 and up.

How to use it

The core interfaces of Factorium are Generator, Factory, and Modifier. Generators are the core of this framework, and in fact, factories are also just groups of generators with some sauce on top. Modifiers serve to optionally modify a new object before it is returned.

Generators

A generator's job is to create an object and apply modifiers to it. A new object with random values should be generated at each new call to its methods. To simplify the application of modifiers, the BaseGenerator abstract class is provided.

It is recommended to always extend from BaseGenerator or one of its subclasses when creating a generator as it guarantees protection against possible (unlikely) future API changes.

The FakerGenerator is a BaseGenerator with a static faker instance to simplify the creation of objects with random data. All examples in this readme assume usage of the FakerGenerator.

Simply create a subclass of BaseGenerator (or FakerGenerator) and implement the protected T make() method. Like so:

public class CityGenerator extends FakerGenerator<City> {
    @Override
    protected City make() {
        return new City(faker.name().lastName(), Math.abs(faker.random().nextLong()) + 1);
    }
}

And call it like:

    City foo = new CityGenerator().generate();

But what if I want to have specialized versions of my generator for different scenarios? Simple, just create a new generator. I suggest keeping generators for a same class, in the same class with the outer class being the default generator.

public class CityGenerator extends FakerGenerator<City> {
    /**
     * Suggested key for the default city generator.
     */
    public static String KEY = "default";

    @Override
    protected City make() {
        return new City(faker.name().lastName(), Math.abs(faker.random().nextLong()) + 1);
    }

    public static class CapitalGenerator extends FakerGenerator<City> {
        /**
         * Suggested key for the capital city generator.
         */
        public static String KEY = "capital";

        @Override
        protected City make() {
            return new City(faker.country().capital(), Math.abs(faker.random().nextLong()) + 1);
        }
    }
}

Cool, but I want like, 5 cities. How do I do that? Just give an int as your first argument to the generator you call.

    List<City> cities = new CityGenerator().generate(5);

Modifiers

Modifiers modify a new object before it is returned to the caller. There are two modifiers provided out of the box:

• FieldMod
• MethodMod

Note that you may add as many modifiers, one after the other, to a generate() call. If you generate multiple objects at the same time, all the modifiers will be applied to all the objects.

    City city = new CityGenerator().generate(new FieldMod("nCitizens", 5), new MethodMod("setName", "Toronto"));

Note that modifiers are usually applied after the object has been created.

Factories

Factories are groups of generators that produce the same kind of output. They may be used to decorate your generators. For example, the RecordingFactory registers all the objects its generators create, which can be useful if you want to test a DAO.

A Factory is a Generator. To accomplish this contract, it must have a default generator that will be used when no specific generator key is given.

The easiest way to create a Factory is by using the BaseFactory class and implementing it's decorate(T, Modifier[]) method.