Chainable framework apex

gistfile1.txt

public abstract class Chainable implements Queueable {
    private Chainable next;
    private ChainableContext context;

    public Chainable() {
        this.context = new BaseContext();
    }

    protected abstract void execute(ChainableContext context);

    public Chainable enqueue(Chainable next) {
        if (this.next == null) {
            this.next = next;
        } else {
            this.next.enqueue(next);
        }
        return this;
    }
    protected void setContext(ChainableContext context) {
        this.context = context;
    }

    public void execute(QueueableContext context) {
        execute(this.context);
        if (next != null) {
            next.setContext(this.context);
            System.enqueueJob(next);
        }
    }

    public interface ChainableContext {
        Object getContext();
    }

    public class BaseContext implements ChainableContext {
        public Object getContext() {
            return null;
        }
    }
}