1 * serializer.write(_, "a")

        when: // same value is not written
        def r = cache.maybeUpdate { it }

        then:
        r == "a"
        1 * serializer.read(_)

        and:
        0 * serializer.write(_, _)

        when: // different value is written back
        r = cache.maybeUpdate { "b" }

        then:
        1 * serializer.read(_)

        and:

    public T update(final UpdateAction<T> updateAction) {
        return doUpdate(updateAction, () -> delegate.update(updateAction));
    }

    @Override
    public T maybeUpdate(final UpdateAction<T> updateAction) {
        return doUpdate(updateAction, () -> delegate.maybeUpdate(updateAction));
    }

    private T doUpdate(UpdateAction<T> updateAction, Supplier<T> work) {
        try {
            return work.get();

                } else {
                    result = oldValue;
                }
            }
        }

        MaybeUpdater maybeUpdater = new MaybeUpdater(updateAction);
        fileAccess.updateFile(maybeUpdater);
        return maybeUpdater.result;
    }

    private void serialize(T newValue) {
        try {
            if (!cacheFile.isFile()) {