Java ばらばらの文字コードを一括で同じ文字コードに変換

Java ファイルのばらばらの文字コードを一括で同じ文字コードに変換して保存

    public void writeFile() throws IOException {
        Files.list(Paths.get("dir"))
            .filter(p -> p.toFile().getName().endsWith(".txt"))
            .forEach(p -> writeFile(p));

        Files.find(Paths.get("dir")
                , Integer.MAX_VALUE
                , (p, a) -> p.toFile().getName().endsWith(".txt"))
            .forEach(p -> writeFile(p));
    }

    public void writeFile(Path path) {
        try {
            Files.write(path
                    , readFile(path).stream().collect(Collectors.joining("\r")).getBytes(StandardCharsets.UTF_8));
        } catch (IOException e) {
            throw new IllegalStateException("write error file : " + path.toAbsolutePath(), e);
        }
    }

    public List<String> readFile(Path path) {
        for (Charset charset: Charset.availableCharsets().values()) {
            try {
                return Files.readAllLines(path, charset);
            } catch (MalformedInputException e) {
                e.printStackTrace();
                continue;
            } catch (IOException e) {
                throw new IllegalStateException("read error file : " + path.toAbsolutePath(), e);
            }
        }
        throw new IllegalStateException("read error file : " + path.toAbsolutePath());
    }