Java.io.EOFException in Object file transfer

Question

Greetings,
I am having a problem sending a file across a network. At one point it was working, however I am not sure where along the way it became broken.
Stack Trace:
java.io.EOFException
at java.io.ObjectInputStream$PeekInputStream.readFully(Unknown Source)
at java.io.ObjectInputStream$BlockDataInputStream.readShort(Unknown Sour
ce)
at java.io.ObjectInputStream.readStreamHeader(Unknown Source)
at java.io.ObjectInputStream.<init>(Unknown Source)
at WBServer.unpackVectors(WBServer.java:283)
at fileListener.run(WBServer.java:374)
    public void getWBContent(String hid) throws java.rmi.RemoteException //<- Send all object vectors and relevant integers...
        setPageNum(pageCount-1);
        HID=hid;
        packVectors(null);
        new Thread() {
            public void run(){
               try{javax.swing.SwingUtilities.invokeLater(
               new Runnable(){
                   public void run(){
                        try{ //Yes...
                            java.net.Socket s = new java.net.Socket(HID, 1113); //<- Make a network port
                            java.io.BufferedWriter sos = new java.io.BufferedWriter(new java.io.OutputStreamWriter(s.getOutputStream())); //<-Open a stream
                            sos.write("vectordata.dat"); //<-Send the name of the file
                            sos.close(); //<- Close the stream
                            s.close(); //<- Close the port
                            String anchor = getClass().getResource("WBServer.class").getPath();
                            java.net.Socket ns = new java.net.Socket(HID, 1113); //<- Open a new port to the same place
                            java.io.FileInputStream fio = new java.io.FileInputStream(anchor.substring(0, anchor.lastIndexOf('/')+1)+"vectordata.dat"); //<- Open the file to stream
                            //java.io.DataInputStream dia = new java.io.DataInputStream(fio); //<- Open the stream to read
                            java.io.BufferedInputStream bia = new java.io.BufferedInputStream(fio);
                            java.io.BufferedOutputStream boa = new java.io.BufferedOutputStream(ns.getOutputStream());//<- Open the data stream for the port
                            int read=0; //<- Byte Read Counter
                            byte[] fbuffer = new byte[1024]; //<- Byte Read Buffer
                            boolean EOF=false;
                            while(!EOF){ //<- Until we reach the end of the stream...
                                try{read=bia.read(fbuffer);
                                boa.write(fbuffer, 0, read);} //<- ...send the number of bytes stored in the buffer at the time.
                                catch(java.io.EOFException e){ EOF=true;}
                            boa.flush(); //<- Make sure the stream is cleared
                            boa.close(); //<- Close the port's stream
                            bia.close(); //<- Close the reading stream
                            fio.close(); //<- Close the file's stream
                            ns.close(); //<- Close the port...
                        catch(Exception e)
                        {SimpleFormatter sf = new SimpleFormatter();
                         LogRecord tempLog = new LogRecord(Level.WARNING, "File Send Error: "+e.toString());
                         sf.format(tempLog);
                         logFile.publish(tempLog);}
                catch(Exception e)
                {SimpleFormatter sf = new SimpleFormatter();
                 LogRecord tempLog = new LogRecord(Level.WARNING, "Error running getWBContent() send file thread: "+e.toString());
                 sf.format(tempLog);
                 logFile.publish(tempLog);}
            }}.start();
    public void packVectors(String filePath) {   //This function writes all the objects in memory to a file for transport.
        String anchor = getClass().getResource("WBServer.class").getPath();
        if(filePath==null){filePath=anchor.substring(0, anchor.lastIndexOf('/')+1)+"data/vectordata.dat";}
        System.out.println("From packVectors(): "+filePath);
        java.io.File ovFile = new java.io.File(filePath); //Setup out data file
        try{if(!ovFile.exists()){ovFile.createNewFile();}else{ovFile.delete(); ovFile.createNewFile();} //If it's not there...make one. If it is, delete it and make a new one.
        java.io.ObjectOutputStream oojStream = new java.io.ObjectOutputStream(new java.io.FileOutputStream(ovFile)); //Ready the writer for writingness.
        oojStream.writeObject(PageHolder); //Pages to file...
        oojStream.writeObject(ImgPage); //Images for the Pages to file...
        oojStream.writeObject(WBStack); //Current object stack to file...
        oojStream.writeInt(objCount); //Current object count to file...
        oojStream.writeInt(pageCount); //Current page count to file...
        oojStream.writeInt(pageCount-1); //Current page number to file...
        oojStream.flush(); //<-Commit final write operations...
        oojStream.close();} //<- Close the file...
        catch(Exception e)
        {SimpleFormatter s = new SimpleFormatter();
         LogRecord tempLog = new LogRecord(Level.WARNING, "Persistence save error: "+e.toString());
         s.format(tempLog);
         e.printStackTrace();
         logFile.publish(tempLog);}
    public void unpackVectors(String filePath) {   //This function reads objects from a file that was previously written by packVectors().
        String anchor = getClass().getResource("WBServer.class").getPath();
        if(filePath==null){filePath=anchor.substring(0, anchor.lastIndexOf('/')+1)+"data/vectordata.dat";}
        System.out.println("From unpackVectors(): "+filePath);
        java.io.File ivFile = new java.io.File(filePath); //Setup the file to read from.
        try{if(!ivFile.exists()){ //If the file doesn't exist, we're screwed...
            SimpleFormatter s = new SimpleFormatter();
            LogRecord tempLog = new LogRecord(Level.WARNING, "Persistence load error: File vectordata.dat does not exist!");
            s.format(tempLog);
            logFile.publish(tempLog);
        }else{
            java.io.ObjectInputStream iojStream = new java.io.ObjectInputStream(new java.io.FileInputStream(ivFile)); //Ready the reader for readingness...
            PageHolder = (java.util.Vector)iojStream.readObject(); //Pages from file...
            ImgPage = (java.util.Vector)iojStream.readObject(); //images for Pages from file...
            WBStack = (java.util.Vector)iojStream.readObject(); //Current object stack from file...
            objCount = iojStream.readInt(); //Current object count from file...
            pageCount = iojStream.readInt(); //Current number of pages from file...
            pageNum = iojStream.readInt();//iojStream.readInt(); //Current page number from file...
            iojStream.close();}} //Close the file...
        catch(Exception e)// We screwed up somewhere.....
        {SimpleFormatter s = new SimpleFormatter();
         LogRecord tempLog = new LogRecord(Level.WARNING, "Persistence load error: "+e.toString());
         s.format(tempLog);
         e.printStackTrace();
         logFile.publish(tempLog);}
class fileListener extends Thread {
    public fileListener(WBServer wb) //<-Constructor
        try{ms = new java.net.ServerSocket(1113);} //<- Listener socket
        catch(Exception e){e.toString();}
        server = wb; //<- Referencial variable back to the server
    public fileListener(WBServer wb, int port) //<- Constructor with port
        try{ms = new java.net.ServerSocket(port);} //<- Listener socket
        catch(Exception e){e.toString();}
        server = wb; //<- Referencial variable back to the server
    public void run() {
        String filepath; //<- Holder for file path operations...
        while(!disconnect) {
            try{java.net.Socket cs = ms.accept(); //<- Accept incoming request.
            server.fileStat = 1;
            java.io.BufferedReader str = new java.io.BufferedReader(new java.io.InputStreamReader(cs.getInputStream())); //<- Open communications with client
            String checkStr = str.readLine(); //<- Grab the file name from the client
            System.out.println(checkStr);
            String anchor = getClass().getResource("fileListener.class").getPath();
            if(checkStr.equalsIgnoreCase("vectordata.dat"))
            {filepath=anchor.substring(0, anchor.lastIndexOf('/')+1)+"data/"+checkStr;}
            else{filepath=anchor.substring(0, anchor.lastIndexOf('/')+1)+"scans/"+checkStr;}
            System.out.println(filepath);
            str.close(); //<- Close communications with client
            cs.close(); //<- Close socket
            //System.out.println("Recieved File Name: "+filepath);//Debugging
            java.io.File inFile = new java.io.File(filepath); //<- Make a file in memory on the host computer with the specified name.
            inFile.createNewFile(); //<- Create an empty file of that name within the local file system
            java.net.Socket ds = ms.accept(); //<- Accept incoming request
            java.io.FileOutputStream fos = new java.io.FileOutputStream(inFile); //<- Open file stream for writing...
            java.io.BufferedInputStream bis = new java.io.BufferedInputStream(ds.getInputStream()); //<- Open communications with client for data/
            byte[] fbuffer = new byte[1024]; //<- Byte read buffer
            int read=0; //<- Byte read counter
            server.fileStat = 2;
            while((read=bis.read(fbuffer))!=-1){ //<-Until we reach the end of the stream...
                fos.write(fbuffer, 0, read); System.out.print(read+":");}// <- ...write the buffer to the file.
            fos.flush(); //<- Clear the file stream
            fos.close(); //<- Close the file stream
            bis.close(); //<- Close the data stream from the client
            if(checkStr.equalsIgnoreCase("vectordata.dat"))
            {server.fileStat = 3; // ...otherwise, we show loading...
             server.unpackVectors(null);
             server.sendRefresh(true);
             server.fileStat=0;}
            else //If it's the sych data, unpack it and load the data
            {server.fileStat = 3; // ...otherwise, we show loading...
             server.passImage(inFile); //<-Load the file into the image vector...
             server.sendRefresh(true); //<- Ensure that the client updates properly
             server.fileStat=0;}
            ds.close(); //<- Close the client socket
            catch(Exception e){e.toString();}
        //System.out.println("Listener Shutdown");//Debugging
        try{ms.close();} catch(Exception e){e.toString();} //<- Close the listening socket
    public boolean disconnect = false; //<- Flag for killing the "file server" prematurely
    private static WBServer server; //<- Referencial variable to the whiteboard server
    private java.net.ServerSocket ms; //<- Listener socket
}I'm stumped as to where it is going wrong. I know that packVectors() and unpackVectors() both work, as they are used in a local save function. I suspect the problem lies between the getWBContent(String hid) and the fileListener class, but I am not certain where. Any help would be appreciated.

Answer 1

First, you are expecting read(buffer,offset,count) to throw an EOFException. It doesn't, it returns -1 at EOF.
Second, you are using a Writer to write binary data (resulting from serialization). This will corrupt it. Use an OutputStream.
Third, what I really don't get is why would you (i) write local data to a file and (ii) start a new thread to (iii) read it back and (iv) send it over not one but two sockets, when you could just return the data as the result of the remote method without the file, the thread, or the Sockets.
And in any case this sort of thing is most definitely not what SwingtUtilites.invokeLater() is for. (What it is for is updating Swing components and ensuring it all happens in the Swing thread, being the only correct way to write Swing code as Swing is not thread-safe by design.) If your server has a Swing GUI, which doesn't seem likely, it will stall for the duration of all this I/O. If it doesn't, why start the Swing thread at all?
Just define a serializable object that contains all the data you are passing to writeObject()/writeInt() and return it as the result of the remote method.
You will save yourself a lot of latency and code in the process, and you could reduce all this to about six lines of code, something like:
return new WBContent(
PageHolder, //Pages to file...
ImgPage, //Images for the Pages to file...
WBStack, //Current object stack to file...
objCount, //Current object count to file...
pageCount, //Current page count to file...
pageCount-1 //Current page number to file...
); where WBContent is a serializable class with the appropriate members and constructor, and is the return type of getWBContent().