public void addPath(final Block callerBlock, final Block returnBlock) {
		for (int i = 0; i < paths.size(); i++) {
			final Block[] path = (Block[]) paths.get(i);
			if (path[0] == callerBlock) {
				path[1] = returnBlock;
				return;
			}
		}

		paths.add(new Block[] { callerBlock, returnBlock });
	}