GuiTaskRunner.java

    /**
     * Run a task in the background producing a value; schedule a task consuming
     * that value to run on the UI thread
     *
     * @param supplier the background task producing a value
     * @param consumer the UI thread task consuming that value
     * @param <T> type parameter of the produced/consume value
     */
    public <T> void compute(
        @OnBackgroundThread final Supplier<? extends T> supplier,
        @OnUiThread final Consumer<? super T> consumer)
    {
        Objects.requireNonNull(supplier);
        Objects.requireNonNull(consumer);

        executor.submit(() -> {
            final T t = supplier.get();
            frontExecutor.execute(() -> consumer.accept(t));
        });
    }