try  {
        Stream<Path> path = Files.walk(sourceDir).filter(p -> p.toString().endsWith(".cpp"));
            path.forEach(filePath -> {
                if (Files.isRegularFile(filePath)) {
                    sourcePaths.add(filePath);
                }
            });

            Stream<Path> path = Files.walk(sourceDir).filter(p -> p.toString().endsWith(".c"));
            path.forEach(filePath -> {
                if (Files.isRegularFile(filePath)) {
                    sourcePaths.add(filePath);
                }
            });

            Stream<Path> path = Files.walk(sourceDir).filter(p -> p.toString().endsWith(".hpp"))
            path.forEach(filePath -> {
                if (Files.isRegularFile(filePath)) {
                    headerPaths.add(filePath);
                }
            });

            Stream<Path> path = Files.walk(sourceDir).filter(p -> p.toString().endsWith(".h"));

            path.forEach(filePath -> {
                if (Files.isRegularFile(filePath)) {
                    headerPaths.add(filePath);
                }
            });

        } catch (IOException e) {
            e.printStackTrace();
        }