Check out example codes for "how to know if a file is iso-8859-1 encoded in java". It will help you in understanding the concepts better.

Code Example 1

FileInputStream fIn  = new FileInputStream(myFile);
            byte[] buf = new byte[4096];
            UniversalDetector detector = new UniversalDetector(null);
            int nread;
            while ((nread = > 0 && !detector.isDone()) {
                detector.handleData(buf, 0, nread);
            String encoding = detector.getDetectedCharset();
            String chartsetName = null;
            if (encoding.equalsIgnoreCase("WINDOWS-1252")){
                chartsetName = "ISO-8859-1";
            if (encoding.equalsIgnoreCase("UTF-8")){
                chartsetName = "UTF-8";

            BufferedReader myReader = new BufferedReader(new InputStreamReader(fIn, chartsetName));

Learn ReactJs, React Native from