String (String projectPathStr, String filePathStr) { if (filePathStr.startsWith("/")) return filePathStr; List<String> path = new ArrayList<>(StringUtil.split(projectPathStr, "/")); StringBuilder prefix = new StringBuilder(); while (!filePathStr.startsWith(StringUtil.join(path, "/"))) { prefix.append(path.remove(0)).append("/"); if (path.isEmpty()) return null; } return prefix.append(filePathStr).toString(); }