Reset input stream

Question

Is there any way to mark/reset (or something comparable) an input stream that does not support the actual mark/reset methods? I'm using a DataInputStream, which contains a FileInputStream, and I've gotten an IOException saying mark/reset is not supported. Is there any other way to do it?

Answer 1

I'm basically just reading bytes of binary data from a file, and I want to include a feature to reset and start reading again from the beginning. here's some of my code:
public static void readWithDelay() {
        byte buf[] = new byte[100000];
        byte skipbytes[] = new byte[2];
        int length = 0, prevtime, time, lastprevtime=0, num=0, timecheck,skiplength=0;
        long period, filesize=0, bytecount = 0;
        double val = 0.0;
        try {
            begin = System.currentTimeMillis();
            // open the .pgem file stream
            try {
                binfile = new DataInputStream(new FileInputStream(getFname()));
            } catch (Exception e) {
                JOptionPane.showMessageDialog(new JFrame(), "File not Found. Try Again.", "Open File error", JOptionPane.ERROR_MESSAGE);
            try {
                File file = new File(getFname());
                filesize = file.length();
            } catch (Exception e) {
                e.printStackTrace();
            try {
                // open the socket to socket on localhost
                Socket socket = new Socket(getText(), port);  // 1222 is TagBrowsers port
                socket.setTcpNoDelay(true); // Disable TCP Nagle algorithm
                socketOutputStream = new DataOutputStream(socket.getOutputStream());
            } catch (UnknownHostException u) {
                JOptionPane.showMessageDialog(new JFrame(), "Host Not Found. Defaulting to localhost", "Socket error", JOptionPane.ERROR_MESSAGE);
                Socket socket = new Socket("localhost", 1222);  // 1222 is TagBrowsers port
                socket.setTcpNoDelay(true); // Disable TCP Nagle algorithm
                socketOutputStream = new DataOutputStream(socket.getOutputStream());
            bos = new BufferedOutputStream(socketOutputStream, 10000);
            // loop copying file to output buffer until endfile
            rate=rate/10;
            start();
            begin = System.currentTimeMillis();
            //binfile.mark(500000000); <<<<<Tried to mark it here>>>>
            for (int i=0;i<24;i++) {
                buf[i] = binfile.readByte();
                bytecount++;
            time = ((buf[6] & 0xff) << 24) | ((buf[7] & 0xff) << 16) | ((buf[8] & 0xff) << 8) | (buf[9] & 0xff);
            length = ((buf[14] & 0xff) << 8) | (buf[15] & 0xff);
            for (int i=24;i<24+length;i++) {
                buf[i] = binfile.readByte();
                bytecount++;
            prevtime = time;
            try {                       // While !end of file
                while (true && !stopXfer) {
                    while (prevtime == time) {
                        while (pause)
                            Thread.sleep(15);
                        bos.write(buf,0,24 + length);
                        prevtime = time;
                        for (int i=0;i<24;i++) {
                            buf[i] = binfile.readByte();
                            bytecount++;
                        time = ((buf[6] & 0xff) << 24) | ((buf[7] & 0xff) << 16) | ((buf[8] & 0xff) << 8) | (buf[9] & 0xff);
                        length = ((buf[14] & 0xff) << 8) | (buf[15] & 0xff);
                        for (int i=24;i<24+length;i++) {
                            buf[i] = binfile.readByte();
                            bytecount++;
                      /*  if (rewind) {
                            binfile.reset();    <<<<Reset here>>>>>
                            rewind = false;
                        while (fastforward) {
                            binfile.skip(14);
                            bytecount+=24;
                            skipbytes[0] = binfile.readByte();
                            skipbytes[1] = binfile.readByte();
                            skiplength = ((skipbytes[0] & 0xff) << 8) | (skipbytes[1] & 0xff);
                            binfile.skip(8+skiplength);
                            bytecount+=10+length;
                            val = (double)(bytecount)/(double)(filesize);
                            updateDelayProgress((int)(val*100));
                            //System.out.println(bytecount);
                        // if times are out of order, flush buffer right away
                        if (time < prevtime || time==lastprevtime) {
                            period = 0;
                            bos.flush();
                            timecheck = prevtime;
                            prevtime = time;
                    if (lastprevtime > prevtime)
                        prevtime = lastprevtime;
                    period = (long) (time - prevtime);
                    try {
                        bos.flush();
                        stop();
                        if (period < elapsedTime || period > 750)
                            period=elapsedTime;
                        val = (double)(bytecount)/(double)(filesize);
                        updateDelayProgress((int)(val*100));
                        Thread.sleep((int)(rate*(period - elapsedTime)));
                        reset();
                        start();
                    } catch(InterruptedException ie){
                        System.out.println("Problem with thread");
                        System.exit(1);
                    prevtime = time;
                    lastprevtime = time;
                    timecheck = time;
            } catch (EOFException e) {
            } catch (SocketException s) {
                System.out.println("Transmission ended");
            } catch (Exception e) {
                e.printStackTrace();
            // Close input stream and display dialog with total duration of the read and transfer
            try {
                minutes = (((System.currentTimeMillis() - begin)/1000) / 60);
                seconds = (((System.currentTimeMillis() - begin)/1000) % 60);
                binfile.close();
                bos.close();
                JOptionPane.showMessageDialog(new TBCGUI(), "Read completed in " + minutes + " minutes, " + seconds + " seconds");
                getFrame().validate();
            } catch (Exception e) {
                System.err.println(e);
                e.printStackTrace();
        } catch (Exception e) {}
    }