Urgent help:send image over network using rmi

Question

hi all,
i have few question about send image using rmi.
1) should i use ByteArrayOutputStream to convert image into byte array before i send over network or just use fileinputstream to convert image into byte array like what i have done as below?
public class RemoteServerImpl  extends UnicastRemoteObject implements RemoteServer
  public RemoteServerImpl() throws RemoteException
  public byte[] getimage() throws RemoteException
    try{
       // capture the whole screen
       BufferedImage screencapture = new Robot().createScreenCapture(new     Rectangle(Toolkit.getDefaultToolkit().getScreenSize()) );
       // Save as JPEG
       File file = new File("screencapture.jpg");
       ImageIO.write(screencapture, "jpg", file);
        byte[] fileByteContent = null;
       fileByteContent = getImageStream("screencapture.jpg");
       return fileByteContent;
    catch(IOException ex)
  public byte[] getImageStream(String fname) // local method
    String fileName = fname;
    FileInputStream fileInputStream = null;
    byte[] fileByteContent = null;
      try
        int count = 0;
        fileInputStream = new FileInputStream(fileName);  // Obtains input bytes from a file.
        fileByteContent = new byte[fileInputStream.available()]; // Assign size to byte array.
        while (fileInputStream.available()>0)   // Correcting file content bytes, and put them into the byte array.
           fileByteContent[count]=(byte)fileInputStream.read();
           count++;
       catch (IOException fnfe)
     return fileByteContent;           
}2)if what i done is wrong,can somebody give me guide?else if correct ,then how can i rebuild the image from the byte array and put it in a JLable?i now must use FileOuputStream but how?can anyone answer me or simple code?
thanks in advance..

Answer 1

Hi! well a had the same problem sending an image trough RMI.. To solve this i just read the image file into a byte Array and send the array to the client, and then the client creates an imegeIcon from the byte Array containing the image.. Below is the example function ton read the file to a byte Array (on the server) and the function to convert it to a an imageIcon (on the client).
//      Returns the contents of the file in a byte array.
    public static byte[] getBytesFromFile(File file) throws IOException {
        InputStream is = new FileInputStream(file);
        // Get the size of the file
        long length = file.length();
        // You cannot create an array using a long type.
        // It needs to be an int type.
        // Before converting to an int type, check
        // to ensure that file is not larger than Integer.MAX_VALUE.
        if (length > Integer.MAX_VALUE) {
            // File is too large
        // Create the byte array to hold the data
        byte[] bytes = new byte[(int)length];
        // Read in the bytes
        int offset = 0;
        int numRead = 0;
        while (offset < bytes.length
               && (numRead=is.read(bytes, offset, bytes.length-offset)) >= 0) {
            offset += numRead;
        // Ensure all the bytes have been read in
        if (offset < bytes.length) {
            throw new IOException("Could not completely read file "+file.getName());
        // Close the input stream and return bytes
        is.close();
        return bytes;
    }to use this function simply use something like this
public byte[] getImage(){
byte[] imageData;
          File file = new File("pic.jpg");
          // Change pic.jpg for the name of your file (duh)
          try{
               imageData = getBytesFromFile(file);
               // Send to client via RMI
                        return imageData;
          }catch(IOException ioe){
                       // Handle exception
                       return null; // or whatever you want..
}and then on the client you could call a function like this
public ImageIcon getImageFromServer(){
     try{
          // get the image from the RMI server
          byte[] imgBytes = myServerObject.getImage();
          // Create an imageIcon from the Array of bytes
          ImageIcon ii = new ImageIcon(imgBytes);
          return ii;
     }catch(Exception e){
          // Handle some error..
          // If yo get here probably something went wrong with the server
          // like File Not Found or something like that..
          e.printStackTrace();
          return null;
}Hope it helps you..