How to make a GUI client to download a file in java

Question

How to make a GUI client to download a file in java

Please help me. I want to make a GUI application that uploads a file from a client to a server. when I click the browse button, then the file is copied as bytes, because we move the data in bytes on the network, but when I click the "Download" button, then the file cannot be downloaded.

import javax.swing.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;

class ClientUpload extends JFrame implements ActionListener {

    JFileChooser fc;
    JButton b, b1;
    JTextField tf;
    FileInputStream in;
    Socket s;
    DataOutputStream dout;
    DataInputStream din;
    int i;

    ClientUpload() {
        super("client");
        tf = new JTextField();
        tf.setBounds(20, 50, 190, 30);
        add(tf);

        b = new JButton("Browse");
        b.setBounds(250, 50, 80, 30);
        add(b);
        b.addActionListener(this);
        b1 = new JButton("Upload");
        b1.setBounds(250, 100, 80, 30);
        add(b1);
        b1.addActionListener(this);
        fc = new JFileChooser();
        setLayout(null);
        setSize(400, 300);
        setVisible(true);
        try {
            s = new Socket("localhost", 10);
            dout = new DataOutputStream(s.getOutputStream());
            din = new DataInputStream(s.getInputStream());
            send();
        } catch (Exception e) {
        }
    }

    public void actionPerformed(ActionEvent e) {
        try {
            if (e.getSource() == b) {
                int x = fc.showOpenDialog(null);
                if (x == JFileChooser.APPROVE_OPTION) {
                    copy();
                }
            }
            if (e.getSource() == b1) {
                send();
            }
        } catch (Exception ex) {
        }
    }

    public void copy() throws IOException {
        File f1 = fc.getSelectedFile();
        tf.setText(f1.getAbsolutePath());
        in = new FileInputStream(f1.getAbsolutePath());
        while ((i = in.read()) != -1) {
            System.out.print(i);
        }
    }

    public void send() throws IOException {
        dout.write(i);
        dout.flush();

    }

    public static void main(String... d) {
        new ClientUpload();
    }
}

+1

java user-interface swing serversocket

AR7 Oct 3 '13 at 6:29

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2 answers

MadProgrammer · Answer 1 · 2013-10-03T06:50:28+0000

Basically, you read the contents of the file when you select it, discard the contents, and then try to send the last value intthat you read on it to the server. The my file will be many, many, many bytes (think giga bytes), intnot going to store this information (bad int).

, File, , ...

public void actionPerformed(ActionEvent e) {
    try {
        if (e.getSource() == b) {
            int x = fc.showOpenDialog(null);
            if (x == JFileChooser.APPROVE_OPTION) {
                fileToBeSent = fc.getSelectedFile();
                tf.setText(f1.getAbsolutePath());
                b1.setEnabled(true);
            } else {
                fileToBeSent = null;
                tf.setText(null;);
                b1.setEnabled(false);
            }
        }
        if (e.getSource() == b1) {
            send();
        }
    } catch (Exception ex) {
    }
}

"", ...

FileInputStream in = null;
try {
    in = new FileInputStream(fileToBeSent);
    byte[] buffer = new byte[1024];
    int bytesIn = -1;
    while ((bytesIn = in.read(buffer)) != -1) {
        dout.write(buffer, 0, bytesIn);
    }
    dout.flush();
} finally {
    try {
        in.close();
    } catch (Exception exp) {
    }
}

.

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Concurrency Swing.

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API- , .

Basic I/O ...

Mano Chella · Answer 2 · 2014-04-09T06:50:37+0000

, ....

package newpack;

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;

public class SwingControlServer extends JFrame {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private JPanel contentPane;

    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    SwingControlServer frame = new SwingControlServer();
                    frame.setVisible(false);
                    frame.start();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    protected static void start() throws IOException {
        // TODO Auto-generated method stub
         System.out.println("Server running...");

            /* Listen on port 5555 */

            ServerSocket server = new ServerSocket(10001);

            /* Accept the sk */

            Socket socket = server.accept();

            System.out.println("Server accepted client");
            InputStream inputStream=socket.getInputStream();
            byte[] readbyte=new byte[(1024*10)*1024];           


            FileOutputStream fileOutputStream=new FileOutputStream("D:/Manoj/hello21.zip");
            int writebyte;
            int count=0;
            while((writebyte=inputStream.read(readbyte))!=-1)
            {
                if(writebyte>0)
                    count+=writebyte;
                fileOutputStream.write(readbyte, 0, writebyte);
            }

            //System.out.println("THE WRITEBYTE VALUE IS "+writebyte+"THE READ BYTE VALUE IS"+count);
            inputStream.close();
            System.out.println("CONNECTION CLOSED");



    }

    /**
     * Create the frame.
     */
    public SwingControlServer() {
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 450, 300);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        contentPane.setLayout(new BorderLayout(0, 0));
        setContentPane(contentPane);


    }


}

package newpack;

import java.awt.*;
import java.awt.event.*;
import java.io.File;
import java.io.FileInputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.net.Socket;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.StringTokenizer;

import javax.swing.*;

import org.apache.commons.io.FileUtils;



public class SwingControlDemo extends JFrame {

   /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private JFrame mainFrame;
   private JPanel controlPanel;
   private String filename;
   private String fname;
   private JProgressBar progressBar;
   private Task task;
   private JButton startButton;
   private JTextArea outputTextArea;
   private JTextField textField;
   private JLabel lblFilename;
   private JButton btnNewButton;
   private JButton btnCancel;
   private JLabel sendinglabel;
   private JLabel starttime;
   private JLabel endtime;
private JLabel sendinglabel1;


   public SwingControlDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      SwingControlDemo  swingControlDemo = new SwingControlDemo();      
      swingControlDemo.showProgressBarDemo();
   }

   private void prepareGUI(){
      mainFrame = new JFrame("Large File Upload");
      mainFrame.setSize(492,400);
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });
      mainFrame.getContentPane().setLayout(null);

      controlPanel = new JPanel();
      controlPanel.setBounds(0, 0, 491, 355);
      mainFrame.getContentPane().add(controlPanel);
      controlPanel.setLayout(null);
      mainFrame.setVisible(true);  
   }



   private void showProgressBarDemo(){
      controlPanel.setLayout(null);

      textField = new JTextField();
      textField.setBounds(125, 26, 105, 31);
      controlPanel.add(textField);
      textField.setColumns(10);

        sendinglabel=new JLabel("FIle is Sending...");
        sendinglabel.setBounds(10, 128, 168, 30);
        sendinglabel.setVisible(false);
        sendinglabel.setFont(new Font("Times New Roman", Font.PLAIN, 12));
        controlPanel.add(sendinglabel);

        sendinglabel1=new JLabel("FIle is Sending...");
        sendinglabel1.setBounds(51, 200, 250, 30);
        sendinglabel1.setVisible(false);
        sendinglabel1.setFont(new Font("Times New Roman", Font.PLAIN, 12));
        controlPanel.add(sendinglabel1);


        endtime = new JLabel("");
        endtime.setBounds(204, 200, 208, 33);
        endtime.setFont(new Font("Times New Roman", Font.PLAIN, 14));
        controlPanel.add(endtime);


        starttime = new JLabel("");
        starttime.setBounds(273, 141, 208, 33);
        starttime.setFont(new Font("Times New Roman", Font.PLAIN, 14));
        controlPanel.add(starttime);

      ProgressMonitor pc=new ProgressMonitor(SwingControlDemo.this, "Running My Program","", 0,10);


                  progressBar = new JProgressBar(0, 100);
                  progressBar.setBounds(62, 158, 146, 31);
                  progressBar.setValue(0);
                  progressBar.setStringPainted(true);
                  controlPanel.add(progressBar);


                  startButton = new JButton("Send");
                  startButton.setBounds(75, 82, 90, 31);
                  startButton.addActionListener(new ActionListener() {
                  private int i;

                @Override

                  public void actionPerformed(ActionEvent e) {

                    task = new Task();                
                    task.start();

                }});

                        controlPanel.add(startButton);

                              outputTextArea = new JTextArea("",5,20);
                              outputTextArea.setVisible(false);
                              outputTextArea.setBounds(51, 200, 164, 94);
                              controlPanel.add(outputTextArea);

                              lblFilename = new JLabel("FileName");
                              lblFilename.setVisible(true);
                              lblFilename.setBounds(10, 26, 105, 31);
                              lblFilename.setFont(new Font("Times New Roman", Font.PLAIN, 14));
                              controlPanel.add(lblFilename);


                              btnNewButton = new JButton("Browse");
                              btnNewButton.setBounds(258, 26, 105, 31);
                              btnNewButton.addActionListener(new ActionListener() {




                                public void actionPerformed(ActionEvent arg0) {

                                    JFileChooser filedilg=new JFileChooser();
                                    filedilg.showOpenDialog(filedilg);
                                    filename=filedilg.getSelectedFile().getAbsolutePath();
                                    textField.setText(filename);

                                    File file1=new File(filename);
                                    fname = file1.getName();           
                                    System.out.println("THE FILE NAME IS "+fname);
                                }
                              });
                              btnNewButton.setFont(new Font("Times New Roman", Font.PLAIN, 14));
                              controlPanel.add(btnNewButton);

                              btnCancel = new JButton("Cancel");
                              btnCancel.setBounds(182, 82, 90, 31);
                              btnCancel.addActionListener(new ActionListener() {

                                @Override
                                public void actionPerformed(ActionEvent arg0) {
                                    // TODO Auto-generated method stub
                                System.exit(0); 
                                }
                            });
                              controlPanel.add(btnCancel);
                              mainFrame.setVisible(true);  
   }

   private class Task extends Thread {    
      public Task(){   }     

    public void run(){       

        PrintStream ps = null;      
        if(filename!=null)
        {
            DateFormat df=new SimpleDateFormat("HH:mm:ss");
            Calendar c=Calendar.getInstance();
            String starttime=df.format(c.getTime());
            System.out.println("Start time: "+starttime);

         try{
//To get current working directory
            String workingdirectory=System.getProperty("user.dir");
            System.out.println(workingdirectory);
//Create folder name as LogFolder in workingdirectory
            File file1=new File(workingdirectory+"\\LogFolder\\");

            File f2 = null;         
            //if folder not present we need to create a folder
            if (!file1.exists()) {
                if (file1.mkdir()) {
                    f2=new File(file1, "abc.txt");
                    System.out.println("Directory is created!");
                } else {
                    System.out.println("Failed to create directory!");
                }

            }f2=new File(file1, "abc.txt");
            ps=new PrintStream(f2);

                /* Try to connect to the server on localhost, port 5555 */
            sendinglabel.setVisible(true);
            SwingControlDemo.this.starttime.setText("Start time: "+starttime);

            JOptionPane.showMessageDialog(rootPane, "File is Sending...!!!");






                Socket socket=new Socket("localhost",10001);

                File file=new File(filename);





                double size=(file.length()/(1024*1024));
                //float size1=(float)size;  

                System.out.println("THE FILE SIZE IS "+size);
                //iterate();



                    byte[] mybyte=new byte[(int) file.length()];

                    FileInputStream fileInputStream=new FileInputStream(file);
                    int count;
                    int i=0;
                    OutputStream outputStream=socket.getOutputStream();

                    while((count=fileInputStream.read(mybyte))!=-1)
                    {
                        outputStream.write(mybyte);
                        i+=1;

                        System.out.print("FIle Sent........"+i+"Kilobytes \t");
                        myFun(i, size);



                }
                System.out.println();

                DateFormat df1=new SimpleDateFormat("HH:mm:ss");
                Calendar c1=Calendar.getInstance();
                String endtime=df1.format(c1.getTime());
                System.out.println("End time is : "+endtime);

                JOptionPane.showMessageDialog(rootPane, "File Sent Successfully!!!!\n Start Time is :"+starttime+"\n End Time Is : "+endtime);
                SwingControlDemo.this.endtime.setText(endtime);
                System.out.println("THIS FILE HAS BEEN SENT SUCCESSFULLY!!!");      



                socket.close();
                System.exit(1);



            }

            catch (Exception ex){
                /* Catch any errors */

                JOptionPane.showMessageDialog(rootPane, "Error While Sending File : "+ex.getMessage());
                ex.printStackTrace(ps);

            }
        }
        else
        {
            JOptionPane.showMessageDialog(rootPane, "Please Choose a Valid File");
        }






      }

    private  void myFun(int j,Double mbsize) {
        // TODO Auto-generated method stub

        int per=(int) ((j*100)/mbsize);
        System.out.println("THE INTEGER VALUE IS "+per);
        if(j<mbsize)
        {
            System.out.println("INSIDE IF LOOP");
            progressBar.setValue(per);

        }
        else
        {
            progressBar.setValue(per);

        }
        try {
            Thread.sleep(10);


         } catch (InterruptedException e) {}

      }

    }
   }

How to make a GUI client to download a file in java

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