Sending and Receiving Information to the UDP Client in Java

Sending and receiving information to the UDP Client in Java

Here, you will provide send and receive information by the UDP client in Java. UDP client sends information or messages to UDP server and it collects some messages from UDP server.

Description of program:

When you will run the program then appears a graphical layout on the screen. Which has destination IP (Internet protocol) address (localhost or 127.0.0.1), destination port number (8080), a text area and a 'Send' command button. All information or messages are written by client in a text area after that you clicked on the 'Send' button then messages to be send into the UDP server and it also sends a message to UDP client in the text area. Therefore UDP client can identify that your sending information are received or not by the UDP server.

Here is the code of program:


import javax.swing.*;

import java.awt.*;

import java.awt.event.*;

import java.net.*;

import java.io.*;



public class RecUDPClient{

  JFrame frame;

  JPanel panel;

  JTextField field1, field2;

  JTextArea area;

  JScrollPane pane;

  JLabel label;

  JButton button;

  public static void main(String[] args) {

    RecUDPClient u = new RecUDPClient();

  }

  public RecUDPClient(){

    frame = new JFrame("Text Client");

    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    frame.setUndecorated(true);

    frame.getRootPane().setWindowDecorationStyle(JRootPane.PLAIN_DIALOG);

    panel = new JPanel();

    panel.setLayout(null);

    label = new JLabel("Desination IP:");

    label.setBounds(10, 20, 100, 30);

    panel.add(label);

    field1 = new JTextField(20);

    field1.setBounds(125, 25, 150, 20);

    panel.add(field1);

    label = new JLabel("Destination Port:");

    label.setBounds(10, 50, 100, 30);

    panel.add(label);

    field2 = new JTextField(10);

    field2.setBounds(125, 55, 100, 20);

    panel.add(field2);

    area = new JTextArea();

    pane = new JScrollPane(area);

    pane.setBounds(10, 100, 300, 200);

    panel.add(pane);

    button = new JButton("Send");

    button.setBounds(235, 310, 75, 30);

    button.addActionListener(new ActionListener(){

      public void actionPerformed(ActionEvent ae){

        new SendRequest();

      }

    });

    panel.add(button);

    frame.add(panel);

    frame.setSize(400, 400);

    frame.setVisible(true);

  }

  public class SendRequest{

    SendRequest(){

      try{

        DatagramSocket socket;

        DatagramPacket packet;

        InetAddress address;

        socket = new DatagramSocket();

        String dip = field1.getText();

        address = InetAddress.getByName(dip);

        String port = field2.getText();

        int pnum = Integer.parseInt(port);

        //For send the message by the client

        String mess = area.getText();

        byte message[] = mess.getBytes();

        packet = new DatagramPacket(message, message.length, address, pnum);

        socket.send(packet);

        area.setText("");

        //For Received message

        packet = new DatagramPacket(message, message.length);

        socket.receive(packet);

        String recmessage = new String(packet.getData());

        area.append("Received
from server: " + recmessage);

          socket.close();

      }

      catch(IOException io){}

    }

  }

}