Socket programming with UDP protocol

package model;

import java.io.Serializable;

public class Customer implements Serializable{
	private static final long serialVersionUID = 20210811004L;
	private int id;
	private String name;
	private String idCard;
	private String address;
	private String tel;
	private String email;
	private String note;
	
	public Customer() {
		super();
	}
	
	public Customer(String name, String idCard, String address, String tel, String email, String note) {
		super();
		this.name = name;
		this.idCard = idCard;
		this.address = address;
		this.tel = tel;
		this.email = email;
		this.note = note;
	}

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getIdCard() {
		return idCard;
	}

	public void setIdCard(String idCard) {
		this.idCard = idCard;
	}

	public String getAddress() {
		return address;
	}

	public void setAddress(String address) {
		this.address = address;
	}

	public String getTel() {
		return tel;
	}

	public void setTel(String tel) {
		this.tel = tel;
	}

	public String getEmail() {
		return email;
	}

	public void setEmail(String email) {
		this.email = email;
	}

	public String getNote() {
		return note;
	}

	public void setNote(String note) {
		this.note = note;
	}
}

package udp.client.view;

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;

import model.IPAddress;
import udp.client.control.ClientCtr;

public class ClientMainFrm extends JFrame implements ActionListener{
	private JMenuBar mnbMain;
	private JMenu mnUser, mnClient;
	private JMenuItem mniLogin, mniEditClient;
	
	private JTextField txtServerHost, txtServerPort, txtClientHost, txtClientPort;
	private JButton btnStart, btnStop;	
	private JTextArea mainText;
	private ClientCtr myControl;
	
	public ClientMainFrm(){
		super("UDP client view");
		
		
		JPanel mainPanel = new JPanel();
		mainPanel.setLayout(null);
		
		mnbMain = new JMenuBar();
		mnUser = new JMenu("User");
		mniLogin = new JMenuItem("Login");
		mniLogin.addActionListener(this);
		mnUser.add(mniLogin);
		mnbMain.add(mnUser);
		
		mnClient = new JMenu("Customer");
		mniEditClient = new JMenuItem("Edit customer");
		mniEditClient.addActionListener(this);
		mnClient.add(mniEditClient);
		mnbMain.add(mnClient);
		this.setJMenuBar(mnbMain);
		mniLogin.setEnabled(false);
		mniEditClient.setEnabled(false);
		
		
		JLabel lblTitle = new JLabel("Client UDP");
		lblTitle.setFont(new java.awt.Font("Dialog", 1, 20));
		lblTitle.setBounds(new Rectangle(150, 20, 200, 30));
		mainPanel.add(lblTitle, null);
		
		JLabel lblHost = new JLabel("Server host:");
		lblHost.setBounds(new Rectangle(10, 70, 150, 25));
		mainPanel.add(lblHost, null);
		
		txtServerHost = new JTextField(50);
		txtServerHost.setBounds(new Rectangle(100, 70, 150, 25));
		mainPanel.add(txtServerHost,null);
		
		JLabel lblPort = new JLabel("Server port:");
		lblPort.setBounds(new Rectangle(10, 100, 150, 25));
		mainPanel.add(lblPort, null);
		
		txtServerPort = new JTextField(50);
		txtServerPort.setBounds(new Rectangle(100, 100, 150, 25));
		mainPanel.add(txtServerPort,null);
		
		JLabel lblClientHost = new JLabel("This client host:");
		lblClientHost.setBounds(new Rectangle(300, 70, 150, 25));
		mainPanel.add(lblClientHost, null);
		
		txtClientHost = new JTextField(50);
		txtClientHost.setText("localhost");
		txtClientHost.setBounds(new Rectangle(420, 70, 150, 25));
		txtClientHost.setEditable(false);
		mainPanel.add(txtClientHost,null);
		
		JLabel lblClientPort = new JLabel("This client port:");
		lblClientPort.setBounds(new Rectangle(300, 100, 150, 25));
		mainPanel.add(lblClientPort, null);
		
		txtClientPort = new JTextField(50);
		txtClientPort.setBounds(new Rectangle(420, 100, 150, 25));
		mainPanel.add(txtClientPort,null);
		
		btnStart = new JButton("Start");
		btnStart.setBounds(new Rectangle(10, 150, 150, 25));
		btnStart.addActionListener(this);
		mainPanel.add(btnStart,null);
		
		btnStop = new JButton("Stop");
		btnStop.setBounds(new Rectangle(170, 150, 150, 25));
		btnStop.addActionListener(this);
		btnStop.setEnabled(false);
		mainPanel.add(btnStop,null);
		
		  		
		JScrollPane jScrollPane1 = new JScrollPane();
		mainText = new JTextArea("");
		jScrollPane1.setBounds(new Rectangle(10, 200, 610, 240));
		mainPanel.add(jScrollPane1, BorderLayout.CENTER);
		jScrollPane1.getViewport().add(mainText, null);
		
		this.setContentPane(mainPanel);
		this.pack();	
		this.setSize(new Dimension(640, 480));
		this.setResizable(false);
		this.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);		
		this.addWindowListener( new WindowAdapter(){
		   public void windowClosing(WindowEvent e) {
		      if(myControl != null) {
		    	  myControl.close();
		      }
		     System.exit(0);
		     }
		  });
	}

	
	@Override
	public void actionPerformed(ActionEvent ae) {
		// TODO Auto-generated method stub
		if(ae.getSource() instanceof JButton) {
			JButton btn = (JButton)ae.getSource();
			if(btn.equals(btnStart)) {// connect button
				if(!txtServerHost.getText().isEmpty() && (txtServerHost.getText().trim().length() > 0) &&
						!txtServerPort.getText().isEmpty() && (txtServerPort.getText().trim().length() > 0)) {//custom server port
					int serverPort = Integer.parseInt(txtServerPort.getText().trim());
					if(!txtClientPort.getText().isEmpty() && (txtClientPort.getText().trim().length() > 0)) {//custom client port
						int clientPort = Integer.parseInt(txtClientPort.getText().trim());
						myControl = new ClientCtr(this, new IPAddress(txtServerHost.getText().trim(), serverPort), clientPort);
					}else {//default client port
						myControl = new ClientCtr(this, new IPAddress(txtServerHost.getText().trim(), serverPort));
					}
				}else {//default server host and port
					if(!txtClientPort.getText().isEmpty() && (txtClientPort.getText().trim().length() > 0)) {//custom client port
						int clientPort = Integer.parseInt(txtClientPort.getText().trim());
						myControl = new ClientCtr(this, clientPort);
					}else {//default client port
						myControl = new ClientCtr(this);
					}
				}
				
				if(myControl.open()) {
					btnStop.setEnabled(true);
					btnStart.setEnabled(false);
					mniLogin.setEnabled(true);
					mniEditClient.setEnabled(true);
				}else {
					if(myControl != null) {
						myControl.close();
						myControl = null;
					}				
					btnStop.setEnabled(false);
					btnStart.setEnabled(true);
					mniLogin.setEnabled(false);
					mniEditClient.setEnabled(false);
				}
			}else if(btn.equals(btnStop)) {// disconnect button
				if(myControl != null) {
					myControl.close();
					myControl = null;
				}				
				btnStop.setEnabled(false);
				btnStart.setEnabled(true);
				mniLogin.setEnabled(false);
				mniEditClient.setEnabled(false);
			}
		}else if(ae.getSource() instanceof JMenuItem) {
			JMenuItem mni = (JMenuItem)ae.getSource();
			if(mni.equals(mniLogin)) {// login function
				
			}else if(mni.equals(mniEditClient)) {// Search client to edit
				SearchCustomerFrm scv = new SearchCustomerFrm(myControl);
				scv.setVisible(true);
			}
		}
	}
	
	public void showMessage(String s){
		  mainText.append("\n"+s);
		  mainText.setCaretPosition(mainText.getDocument().getLength());
	}
	
	public void setServerandClientInfo(IPAddress serverAddress, IPAddress clientAddress) {
		txtServerHost.setText(serverAddress.getHost());
		txtServerPort.setText(serverAddress.getPort()+"");
		txtClientHost.setText(clientAddress.getHost());
		txtClientPort.setText(clientAddress.getPort()+"");
	}	
	
	public static void main(String[] args) {
		ClientMainFrm view = new ClientMainFrm();
		view.setVisible(true);
	}
}

package udp.client.control;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

import model.IPAddress;
import model.ObjectWrapper;
import udp.client.view.ClientMainFrm;


public class ClientCtr {
	private ClientMainFrm view;
	private DatagramSocket myClient;	
	private IPAddress serverAddress = new IPAddress("localhost", 5555); //default server address
	private IPAddress myAddress = new IPAddress("localhost", 6666); //default client address
	
	public ClientCtr(ClientMainFrm view){
		this.view = view;
	}
	
	public ClientCtr(ClientMainFrm view, int clientPort){
		this.view = view;
		myAddress.setPort(clientPort);
	}
	
	public ClientCtr(ClientMainFrm view, IPAddress serverAddr){
		this.view = view;
		serverAddress = serverAddr;
	}
	
	public ClientCtr(ClientMainFrm view, IPAddress serverAddr, int clientPort){
		this.view = view;
		serverAddress = serverAddr;
		myAddress.setPort(clientPort);
	}
	
	
	public boolean open(){
		try {
			myClient = new DatagramSocket(myAddress.getPort());
			myAddress.setHost(InetAddress.getLocalHost().getHostAddress());
			view.setServerandClientInfo(serverAddress, myAddress);
			view.showMessage("UDP client is running at the host: " + myAddress.getHost() + ", port: " + myAddress.getPort());
		}catch(Exception e) {
			e.printStackTrace();
			view.showMessage("Error to open the datagram socket!");
			return false;
		}
		return true;
	}
	
	public boolean close(){
		try {
			myClient.close();
		}catch(Exception e) {
			e.printStackTrace();
			view.showMessage("Error to close the datagram socket!");
			return false;
		}
		return true;
	}
	
	public boolean sendData(ObjectWrapper data){
		try {
			//prepare the buffer and write the data to send into the buffer
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            ObjectOutputStream oos = new ObjectOutputStream(baos);
            oos.writeObject(data);
            oos.flush();            
            
            //create data package and send
            byte[] sendData = baos.toByteArray();
            DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, InetAddress.getByName(serverAddress.getHost()), serverAddress.getPort());
            myClient.send(sendPacket);
			
        } catch (Exception e) {
        	e.printStackTrace();
            view.showMessage("Error in sending data package");
            return false;
        }
		return true;
	}
	
	public ObjectWrapper receiveData(){
		ObjectWrapper result = null;
		try {	
			//prepare the buffer and fetch the received data into the buffer
            byte[] receiveData = new byte[1024];
			DatagramPacket receivePacket = new	DatagramPacket(receiveData, receiveData.length);
			myClient.receive(receivePacket);
			
			//read incoming data from the buffer 
			ByteArrayInputStream bais = new ByteArrayInputStream(receiveData);
		    ObjectInputStream ois = new ObjectInputStream(bais);
			result = (ObjectWrapper)ois.readObject();
        } catch (Exception e) {
        	e.printStackTrace();
            view.showMessage("Error in receiving data package");
        }
		return result;
	}
}

package udp.server.view;

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;

import model.IPAddress;
import udp.server.control.ServerCtr;


public class ServerMainFrm extends JFrame implements ActionListener{
	private JTextField txtServerHost;
	private JTextField txtServerPort;
	private JButton btnStartServer;
	private JButton btnStopServer;	
	private JTextArea mainText;
	private ServerCtr myServer;
	
	public ServerMainFrm(){
		super("UDP server view");
		
		
		JPanel mainPanel = new JPanel();
		mainPanel.setLayout(null);
		
		JLabel lblTitle = new JLabel("Server UDP");
		lblTitle.setFont(new java.awt.Font("Dialog", 1, 20));
		lblTitle.setBounds(new Rectangle(150, 15, 200, 30));
		mainPanel.add(lblTitle, null);
		
		JLabel lblHost = new JLabel("Server host:");
		lblHost.setBounds(new Rectangle(10, 70, 150, 25));
		mainPanel.add(lblHost, null);
		
		txtServerHost = new JTextField(50);
		txtServerHost.setBounds(new Rectangle(170, 70, 150, 25));
		txtServerHost.setText("localhost");
		txtServerHost.setEditable(false);
		mainPanel.add(txtServerHost,null);
		
		JLabel lblPort = new JLabel("Server port:");
		lblPort.setBounds(new Rectangle(10, 100, 150, 25));
		mainPanel.add(lblPort, null);
		
		txtServerPort = new JTextField(50);
		txtServerPort.setBounds(new Rectangle(170, 100, 150, 25));
		mainPanel.add(txtServerPort,null);
		
		btnStartServer = new JButton("Start server");
		btnStartServer.setBounds(new Rectangle(10, 150, 150, 25));
		btnStartServer.addActionListener(this);
		mainPanel.add(btnStartServer,null);
		
		btnStopServer = new JButton("Stop server");
		btnStopServer.setBounds(new Rectangle(170, 150, 150, 25));
		btnStopServer.addActionListener(this);
		btnStopServer.setEnabled(false);
		mainPanel.add(btnStopServer,null);
		
		  		
		JScrollPane jScrollPane1 = new JScrollPane();
		mainText = new JTextArea("");
		jScrollPane1.setBounds(new Rectangle(10, 200, 610, 240));
		mainPanel.add(jScrollPane1, BorderLayout.CENTER);
		jScrollPane1.getViewport().add(mainText, null);
		
		this.setContentPane(mainPanel);
		this.pack();		
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.setSize(new Dimension(640, 480));
		this.setResizable(false);
	}

	public void showServerInfo(IPAddress serverAddr) {
		txtServerHost.setText(serverAddr.getHost());
		txtServerPort.setText(serverAddr.getPort()+"");
	}
	
	@Override
	public void actionPerformed(ActionEvent ae) {
		// TODO Auto-generated method stub
		if(ae.getSource() instanceof JButton) {
			JButton clicked = (JButton)ae.getSource();
			if(clicked.equals(btnStartServer)) {// start button
				if(!txtServerPort.getText().isEmpty() && (txtServerPort.getText().trim().length() > 0)) {//custom port
					int port = Integer.parseInt(txtServerPort.getText().trim());
					myServer = new ServerCtr(this, port);
				}else {// default port
					myServer = new ServerCtr(this);
				}
				if(myServer.open()) {
					btnStopServer.setEnabled(true);
					btnStartServer.setEnabled(false);
				}
			}else if(clicked.equals(btnStopServer)) {// stop button
				if(myServer != null) {
					myServer.close();
					myServer = null;
				}				
				btnStopServer.setEnabled(false);
				btnStartServer.setEnabled(true);
				txtServerHost.setText("localhost");
			}
		}
	}
	
	public void showMessage(String s){
		  mainText.append("\n"+s);
		  mainText.setCaretPosition(mainText.getDocument().getLength());
	}
	
	public static void main(String[] args) {
		ServerMainFrm view = new ServerMainFrm();
		view.setVisible(true);
	}
}

package udp.server.control;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

import jdbc.dao.CustomerDAO;
import jdbc.dao.UserDAO;
import model.Customer;
import model.IPAddress;
import model.ObjectWrapper;
import model.User;
import udp.server.view.ServerMainFrm;


public class ServerCtr {
	private ServerMainFrm view;
	private DatagramSocket myServer;	
	private IPAddress myAddress = new IPAddress("localhost", 5555); //default server address
	private UDPListening myListening;
	
	public ServerCtr(ServerMainFrm view){
		this.view = view;		
	}
	
	public ServerCtr(ServerMainFrm view, int port){
		this.view = view;
		myAddress.setPort(port);
	}
	
	
	public boolean open(){
		try {
			myServer = new DatagramSocket(myAddress.getPort());
			myAddress.setHost(InetAddress.getLocalHost().getHostAddress());
			view.showServerInfo(myAddress);
			myListening = new UDPListening();
			myListening.start();
			view.showMessage("UDP server is running at the host: " + myAddress.getHost() + ", port: " + myAddress.getPort());
		}catch(Exception e) {
			e.printStackTrace();
			view.showMessage("Error to open the datagram socket!");
			return false;
		}
		return true;
	}
	
	public boolean close(){
		try {
			myListening.stop();
			myServer.close();
		}catch(Exception e) {
			e.printStackTrace();
			view.showMessage("Error to close the datagram socket!");
			return false;
		}
		return true;
	}
	
	class UDPListening extends Thread{
		public UDPListening() {
			
		}
		
		public void run() {
			while(true) {				
				try {	
					//prepare the buffer and fetch the received data into the buffer
		            byte[] receiveData = new byte[1024];
		            DatagramPacket receivePacket = new	DatagramPacket(receiveData, receiveData.length);
					myServer.receive(receivePacket);
					
					//read incoming data from the buffer 
					ByteArrayInputStream bais = new ByteArrayInputStream(receiveData);
				    ObjectInputStream ois = new ObjectInputStream(bais);
					ObjectWrapper receivedData = (ObjectWrapper)ois.readObject();
					
					//processing
					ObjectWrapper resultData = new ObjectWrapper();
					switch(receivedData.getPerformative()) {
					case ObjectWrapper.LOGIN_USER:				// login
						User user = (User)receivedData.getData();
						resultData.setPerformative(ObjectWrapper.REPLY_LOGIN_USER);
						if(new UserDAO().checkLogin(user))
							resultData.setData("ok");
						else
							resultData.setData("false");
						break;
					case ObjectWrapper.SEARCH_CUSTOMER_BY_NAME:	// search customer by name
						String key = (String)receivedData.getData();
						resultData.setPerformative(ObjectWrapper.REPLY_SEARCH_CUSTOMER);
						resultData.setData(new CustomerDAO().searchCustomer(key));
						break;
					case ObjectWrapper.EDIT_CUSTOMER: 			// edit customer
						Customer cus = (Customer)receivedData.getData();
						resultData.setPerformative(ObjectWrapper.REPLY_EDIT_CUSTOMER);
						if(new CustomerDAO().editCustomer(cus))
							resultData.setData("ok");
						else
							resultData.setData("false");
						break;
					}
					
					
					//prepare the buffer and write the data to send into the buffer
		            ByteArrayOutputStream baos = new ByteArrayOutputStream();
		            ObjectOutputStream oos = new ObjectOutputStream(baos);
		            oos.writeObject(resultData);
		            oos.flush();            
		            
		            //create data package and send
		            byte[] sendData = baos.toByteArray();
		            DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, receivePacket.getAddress(), receivePacket.getPort());
		            myServer.send(sendPacket);
		        } catch (Exception e) {
		        	e.printStackTrace();
		            view.showMessage("Error when processing an incoming package");
		        }    
			}
		}
	}
}

package jdbc.dao;

import java.sql.Connection;
import java.sql.DriverManager;

public class DAO {
	public static Connection con;
	
	public DAO(){
		if(con == null){
			String dbUrl = "jdbc:mysql://localhost:3307/hotel?autoReconnect=true&useSSL=false";
			String dbClass = "com.mysql.jdbc.Driver";

			try {
				Class.forName(dbClass);
				con = DriverManager.getConnection (dbUrl, "root", "xxx");
			}catch(Exception e) {
				e.printStackTrace();
			}
		}
	}
}

 package jdbc.dao;
import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;
import java.sql.Types;
import java.util.ArrayList;

import model.Customer;

public class CustomerDAO extends DAO{
	
	/**
	 * search all clients in the tblClient whose name contains the @key
	 * using PreparedStatement - recommended for professional coding
	 * @param key
	 * @return list of client whose name contains the @key
	 */
	public ArrayList<Customer> searchCustomer(String key){
		ArrayList<Customer> result = new ArrayList<Customer>();
		String sql = "SELECT * FROM tblclient WHERE name LIKE ?";
		try{
			PreparedStatement ps = con.prepareStatement(sql);
			ps.setString(1, "%" + key + "%");
			ResultSet rs = ps.executeQuery();

			while(rs.next()){
				Customer client = new Customer();
				client.setId(rs.getInt("id"));
				client.setName(rs.getString("name"));
				client.setIdCard(rs.getString("idcard"));
				client.setAddress(rs.getString("address"));
				client.setTel(rs.getString("tel"));
				client.setEmail(rs.getString("email"));
				client.setNote(rs.getString("note"));
				result.add(client);
			}
		}catch(Exception e){
			e.printStackTrace();
		}	
		return result;
	}
	
	/**
	 * update the @client
	 * @param client
	 */
	public boolean editCustomer(Customer client){
		String sql = "UPDATE tblclient SET name=?, idcard =?, address=?, tel=?, email=?, note=? WHERE id=?";
		try{
			PreparedStatement ps = con.prepareStatement(sql);
			ps.setString(1, client.getName());
			ps.setString(2, client.getIdCard());
			ps.setString(3, client.getAddress());
			ps.setString(4, client.getTel());
			ps.setString(5, client.getEmail());
			ps.setString(6, client.getNote());
			ps.setInt(7, client.getId());

			ps.executeUpdate();
		}catch(Exception e){
			e.printStackTrace();
			return false;
		}
		return true;
	}
	
}