public class NioTest13 {

    public static void main(String[] args) throws  Exception {

        String inputFile = "NioTest13_In.txt";

        String outFile = "NioTest13_Out.txt";

        RandomAccessFile inputRandomAccessFile = new RandomAccessFile(inputFile,"r");

        RandomAccessFile outputRandomAccessFile = new RandomAccessFile(outFile,"rw");

        long inputLength = new File(inputFile).length();

        FileChannel inputFileChannel = inputRandomAccessFile.getChannel();

        FileChannel outputFileChannel = outputRandomAccessFile.getChannel();

        MappedByteBuffer inputData = inputFileChannel.map(FileChannel.MapMode.READ_ONLY, 0, inputLength);

        System.out.println("================================");

        /*Charset.availableCharsets().forEach( (k,v) -> {

            System.out.println(k + ", " + v);

        });*/

        System.out.println("================================");

        Charset charset = Charset.forName("iso-8859-1"); //utf-8

        CharsetDecoder decoder = charset.newDecoder(); //字节数组转字符串

        CharsetEncoder encoder = charset.newEncoder(); //字符串转字符数组

        CharBuffer charBuffer = decoder.decode(inputData);

         ByteBuffer outputData = encoder.encode(charBuffer);

        outputFileChannel.write(outputData);

        inputRandomAccessFile.close();

        outputRandomAccessFile.close();

    }

}