private List<MarkListContainer> getAdjacentMarks() {
		List<MarkListContainer> retMarks = new ArrayList<>();

		for (Connection connection : connections) {
			Mark mark = connection.getA();
			if (!mark.equals(this))
				retMarks.add(new MarkListContainer(mark, connection.getType()));
			Mark nextMark = connection.getB();
			if (!nextMark.equals(this))
				retMarks.add(new MarkListContainer(nextMark, connection
						.getType()));
		}
		return retMarks;
	}