Method getExtension

app/src/main/java/eu/faircode/email/Helper.java:2911–2918

(String filename)

    }

    static String getExtension(String filename) {
        if (filename == null)
            return null;
        int index = filename.lastIndexOf(".");
        if (index < 0)
            return null;
        return filename.substring(index + 1);
    }

    static String guessMimeType(String filename) {
        String type = null;