Slug

Slug is a framework for generating flexible data types.

slug-core

Slug allows you to define a loose schema for a set of data by writing an interface for it:

public interface Example extends Slug<Example> {

    String getName();
    void setName(String name);

    Integer getAge();
    Example setAge(Integer age);
}

A SlugBox will generate an implementation of this interface at runtime that's backed by a Map, allowing easy access to the data in the map via the getters and setters defined in the interface, but also allowing you to store and access additional members directly via Slug.get(String) and Slug.set(String, Object), yielding flexibility as schemas evolve over time.

SlugBox box = ...;
Example example = box.create(Example.class);

example.setName("David Murray");
example.set("Job", "Cat Dad");

example.getName();   // "David Murray"
example.get("Name"); // "David Murray"

for (Map.Entry<String, String> entry : example.entrySet()) {
    ...
}

Implementations of the SlugModule interface provide strategies for serializing and deserializing slugs from various wire formats. Slug's loosely-typed model allows it to represent and round-trip data that wasn't part of the schema at the time it was baked, yielding greater flexibility when rolling out upgrades across a distributed system.

SlugModule module = ...;

Object obj = module.deserializeTo(input, Example.class);
if (!(obj instanceof Example)) {
    log.warn("Unexpected data format: " + obj);
    return;
}
Example example = (Example) obj;

if (example.getAge() == null) {
    example.setAge(1);
} else {
    example.setAge(example.getAge() + 1);
}

module.serializeTo(example, output);

slug-json

The JsonSlugModule class is an implementation of SlugModule that serializes to an deserializes from JSON (and similar formats) using Jackson.

JsonFactory factory = ...;
SlugModule module = JsonSlugModule.builder()
    .withJsonFactory(factory)
    .build();

Example example = (Example) module.deserializeTo(data, Example.class);