public <R> EngineResource<R> build(Resource<R> resource, boolean isMemoryCacheable) {
            return new EngineResource<R>(resource, isMemoryCacheable);
        }
A class that manages a load by adding and removing callbacks for for the load and notifying callbacks when the
load completes.
core/src/main/java/com/bumptech/glide/load/engine/EngineJob.java