--- RMI ---

import java.net.*;
import java.rmi.*;
public class RmiServer{
	public static void main(String args[]) throws Exception{
		try{ 
			RmiServerImpl obj = new RmiServerImpl();
			Naming.rebind("s", obj);
		} 
		catch (RemoteException e){
			System.out.println("java RMI registry already exists.");
		}
	}
}

import java.rmi.*;
import java.rmi.server.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
public class RmiServerImpl extends UnicastRemoteObject implements RmiServerIntf{

	JLabel l1;
	JTextArea tf;
	Container c;
	public RmiServerImpl() throws RemoteException{
		display e=new display();
	}
	public class display extends JFrame{
		public display(){
			c =getContentPane();
			FlowLayout f=new FlowLayout();
			c.setLayout(f);
			l1=new JLabel("Received Messages");
			c.add(l1);
			tf=new JTextArea(15,30);
			c.add(tf);
			tf.setText("");
			setVisible(true);	
			setSize(500,500);
			setTitle("Server");
			setDefaultCloseOperation(EXIT_ON_CLOSE);
		}
	}
	public void show(String str) throws RemoteException{
		tf.append("\n"+str); 
	}
}

import java.rmi.*;
public interface RmiServerIntf extends Remote{
	public void show(String str) throws RemoteException;
}

import java.rmi.*;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class RmiClient extends JFrame implements ActionListener{ 
	JLabel l1;
	JTextField tf;
	JButton b1;
	Container c;
	public RmiClient(){
		c =getContentPane();
		FlowLayout f=new FlowLayout();
		c.setLayout(f);
		l1=new JLabel("Message");
		c.add(l1);
		tf=new JTextField(25);
		c.add(tf);
		b1=new JButton("Send");
		c.add(b1);
		b1.addActionListener(this);
		setVisible(true);
		setSize(500,500);
		setTitle("Client");
		setDefaultCloseOperation(EXIT_ON_CLOSE);
	}
	public void actionPerformed(ActionEvent ee){
		try{
			String url="rmi://localhost/s";
			RmiServerIntf obj = (RmiServerIntf)Naming.lookup(url);
			String str=tf.getText();
			obj.show(str);
		}
		catch(Exception e){}
	}
	public static void main(String args[]) throws Exception{
		new RmiClient();
	}
}

-- TCP --

client
import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.net.*;
import java.awt.event.*;
public class client2d extends JFrame implements ActionListener{
	BufferedReader br;
	PrintWriter pw;
	String st,st2;
	JLabel l1;
	JTextField tf;
	JTextArea ta;
	JButton b1;
	Container c;
	Socket skt;
	public client2d(){
		try{
			skt=new Socket("localhost",8000);
			c =getContentPane();
			FlowLayout f=new FlowLayout();
			c.setLayout(f);
			l1=new JLabel("Message");
			c.add(l1);
			tf=new JTextField(25);
			c.add(tf);
			ta=new JTextArea(15,15);
			c.add(ta);
			b1=new JButton("Send");
			c.add(b1);
			b1.addActionListener(this);
			setVisible(true);
			setSize(500,275);
			setTitle("Client");
			setDefaultCloseOperation(EXIT_ON_CLOSE);
			while(true){
				br=new BufferedReader(new InputStreamReader(skt.getInputStream()));
				st2=br.readLine();
				ta.append("\n"+st2);
			}
		}
		catch(Exception e){}
	}
	public void actionPerformed(ActionEvent ee){
		try{
			st=tf.getText();
			pw =  new PrintWriter(skt.getOutputStream(), true);
			pw.println(st);
		}
		catch(Exception e){}
	}
	public static void main(String args[]){
		new client2d();
	}
}

server
import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.net.*;
import java.awt.event.*;
public class server2d extends JFrame implements ActionListener{
	BufferedReader br;
	PrintWriter pw;
	String st,st2;
	JLabel l1;
	JTextField tf;
	JTextArea ta;
	JButton b1;
	Container c;
	ServerSocket ss;
	Socket skt;
	public server2d(){
		try{	
			ss=new ServerSocket(8000);
			skt = ss.accept();
			c =getContentPane();
			FlowLayout f=new FlowLayout();
			c.setLayout(f);
			l1=new JLabel("Message");
			c.add(l1);
			tf=new JTextField(25);
			c.add(tf);
			ta=new JTextArea(15,15);
			c.add(ta);
			b1=new JButton("Send");
			c.add(b1);
			b1.addActionListener(this);
			setVisible(true);
			setSize(500,275);
			setTitle("Server");
			setDefaultCloseOperation(EXIT_ON_CLOSE);
			while(true){
				br=new BufferedReader(new InputStreamReader(skt.getInputStream()));
				st2=br.readLine();
				ta.append("\n"+st2);
			}
		}
		catch(Exception e){}
	}
	public void actionPerformed(ActionEvent ee){
		try{
			st=tf.getText();
			pw =  new PrintWriter(skt.getOutputStream(), true);
			pw.println(st);
		}
		catch(Exception e){}
	}
	public static void main(String args[]){
		new server2d();
	}
}


-- UDP --

server
import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.net.*;
import java.awt.event.*;
public class udpserver extends JFrame implements ActionListener{
	BufferedReader br;
	PrintWriter pw;
	String st,st2;
	JLabel l1;
	JTextField tf;
	JTextArea ta;
	JButton b1;
	Container c;
	DatagramSocket ss,cc;
	DatagramPacket incoming,sending;
	public udpserver() {
		try  {
			ss=new DatagramSocket(8000);
			cc=new DatagramSocket();
			byte [] buffer=new byte[65535];
			incoming=new DatagramPacket(buffer,buffer.length);
			c =getContentPane();
			FlowLayout f=new FlowLayout();
			c.setLayout(f);
			l1=new JLabel("Message");
			c.add(l1);
			tf=new JTextField(25);
			c.add(tf);
			ta=new JTextArea(15,15);
			c.add(ta);
			b1=new JButton("Send");
			c.add(b1);
			b1.addActionListener(this);
			setVisible(true);
			setSize(500,275);
			setTitle("Server");
			setDefaultCloseOperation(EXIT_ON_CLOSE);
			while(true)  {
				ss.receive(incoming);
				byte[] data=incoming.getData();
				st2=new String(data,0,incoming.getLength());
				System.out.println(st2);
				ta.append("\nClient:"+st2);
				setDefaultCloseOperation(EXIT_ON_CLOSE);
			}
		}
		catch(Exception e)
		{}
	}
	public void actionPerformed(ActionEvent ee) {
		try{

			st=tf.getText();
			byte [] b=st.getBytes();
			sending=new DatagramPacket(b,b.length,InetAddress.getLocalHost(),8001);
			ta.append("\nServer:"+st);
			cc.send(sending);
			tf.setText("");
		}
		catch(Exception e) {}
	}
	public static void main(String args[]){
		new udpserver();
	}
}

client
import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.net.*;
import java.awt.event.*;
public class udpclient extends JFrame implements ActionListener{
	BufferedReader br;
	PrintWriter pw;
	String st,st2;
	JLabel l1;
	JTextField tf;
	JTextArea ta;
	JButton b1;
	Container c;
	DatagramSocket ss,cc;
	DatagramPacket incoming,sending;
	byte [] buffer;
	public udpclient()  {
		try {	
			ss=new DatagramSocket(8001);
			cc=new DatagramSocket();
			byte[] buffer=new byte[65535];	
			c =getContentPane();
			FlowLayout f=new FlowLayout();
			c.setLayout(f);
			l1=new JLabel("Message");
			c.add(l1);
			tf=new JTextField(25);
			c.add(tf);
			ta=new JTextArea(15,15);
			c.add(ta);
			b1=new JButton("Send");
			c.add(b1);
			b1.addActionListener(this);
			setVisible(true);
			setSize(500,275);
			setTitle("Client");
			setDefaultCloseOperation(EXIT_ON_CLOSE);
			while(true){
				incoming=new DatagramPacket(buffer,buffer.length);
				ss.receive(incoming);
				byte[] data=incoming.getData();
				st2=new String(data,0,incoming.getLength());
				ta.append("\nServer: "+st2);
				System.out.println(st2);
				setDefaultCloseOperation(EXIT_ON_CLOSE);
			}
		}
		catch(Exception e)  {}
	}
	public void actionPerformed(ActionEvent ee){
		try{	InetAddress in=InetAddress.getByName("localhost");
			st=tf.getText();
			sending=new DatagramPacket(st.getBytes(),st.length(),InetAddress.getLocalHost(),8000);
			ta.append("\nClient:"+st);
			tf.setText("");
			cc.send(sending);		
		}
		catch(Exception e){}
	}

	public static void main(String args[]){
		new udpclient();
	}
}

-- MultiCast --

import java.net.*;
import java.io.*;
class Multicastsender implements Runnable{	
	static int port;
	static MulticastSocket ms;
	static String group;
	Multicastsender() throws Exception{
		port=6789;
		group="224.2.2.9";
		ms=new MulticastSocket(port);
	}
	public void run(){	
		while(true) {
			try{
				BufferedReader br=new BufferedReader(new InputStreamReader (System.in));	
				byte sbuf[]=new byte[300];
				sbuf=br.readLine().getBytes();
				DatagramPacket spack=new DatagramPacket(sbuf,sbuf.length,InetAddress.getByName(group),port);
				ms.send(spack);
			}
			catch(Exception e){}
		}
	}
	public static void main(String args[])throws Exception{	
		Multicastsender sender=new Multicastsender();
		Thread t= new Thread(sender);
		ms.joinGroup(InetAddress.getByName(group));
		t.start();
		int count=0;
		byte rbuf[]=new byte[30];
		System.out.println("MULTICAST SENDER");
		while(true){	
			DatagramPacket rpacket;
			rpacket=new DatagramPacket(rbuf,rbuf.length);
			ms.receive(rpacket);
			String str=new String(rpacket.getData(),0,rpacket.getLength());
			if(str.equals("join")){
				count++;
				System.out.println("Client Joined the group");
				System.out.println("currently "+count+"clients in the group");
			}
			else if(str.equals("leave")){
				count--;
				System.out.println("Client left the group");
				System.out.println("currently "+count+"clients in the group");
			}
			if(count==0){
				ms.leaveGroup(InetAddress.getByName(group));
				break;					
			}
		}
	}
}
reciever
import java.net.*;
import java.io.*;
class Multicastreciever implements Runnable{	
	static int port;
	static MulticastSocket ms;
	static String group;
	public Multicastreciever() throws Exception{
		port=6789;
		ms=new MulticastSocket(port);
	}
	public void run(){
		while(true){	
			try{
				byte rbuf[]=new byte[300];
				DatagramPacket rpack=new DatagramPacket(rbuf,rbuf.length);
				ms.receive(rpack);
				String str=new String(rpack.getData(),0,rpack.getLength());
				if(str.compareTo("join")!=0 && str.compareTo("leave")!=0)
				System.out.println(str);
			}
			catch(Exception e){}
		}
	}
	public static void main(String args[]) throws Exception	{		
		Multicastreciever mr=new Multicastreciever();
		Thread t= new Thread(mr);
		String group="224.2.2.9";
		System.out.println("Do you wish to join");	
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		if(br.readLine().equals("yes"))	{
			ms.joinGroup(InetAddress.getByName(group));
			byte sbuf[]=new byte[30];
			sbuf="join".getBytes();
			DatagramPacket spack=new DatagramPacket(sbuf,sbuf.length,InetAddress.getByName(group),port);
			ms.send(spack);
			System.out.println("client joined the group");
			t.start();
			while(true){	
				String str1=br.readLine();
				if(str1.equals("leave")){
					byte sbuf1[]=new byte[30];
					sbuf1=str1.getBytes();
					DatagramPacket spack1=new DatagramPacket(sbuf1,sbuf1.length, InetAddress.getByName(group),port);
					ms.send(spack1);
					System.out.println("client left the group");
					ms.leaveGroup(InetAddress.getByName(group));
					break;
				}
			}
		}
	}
}


-- SLIDING WINDOW --
sender
import java.io.*; 
import java.net.*; 
class SlidingWindowSender{    	
	public static void main(String argv[]) throws Exception{       
		String msg1;          
		String msg2;
		String buf[]=new String[10];
		int n,sws=3,nf=0,i,b;
		System.out.println("SLIDING WINDOW SENDER");
		Thread.sleep(1000);
		System.out.println("WAITING FOR RECIEVER TO START...");          
		ServerSocket ss = new ServerSocket(8000);          
		Socket s = ss.accept(); 
		System.out.println("RECIEVER STARTED."); 
		do{   
			DataOutputStream op = new DataOutputStream(s.getOutputStream());   
			BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
			BufferedReader br1 = new BufferedReader(new InputStreamReader (s.getInputStream()));
			System.out.println("ENTER THE NUMBER OF FRAMES TO SEND");
			nf=Integer.parseInt(br.readLine());
			if(nf>sws){
				n=sws;
				System.out.println("Enter frames:");
				op.writeBytes(""+n + '\n');
			}
			else{
				n=nf;
				System.out.println("Enter frames:");
				op.writeBytes(""+n + '\n');
			}
			//System.out.println("Enter frames:");
			//op.writeBytes(""+nf + '\n');
			for(i=0;i<n;i++){	
				buf[i]=br.readLine();
				op.writeBytes(buf[i] + '\n');   
			}
			if(n<nf){
				System.out.println("window size exceeds");	
			}
			sws=sws-nf;
			System.out.println("Remaining Window Size:"+sws);
			String ack=br1.readLine();
			if(!ack.equals("")){	
				System.out.println("Acknowledgement Recieved:ACK"+ack);
				sws=sws+nf;
			}
			else{	
				System.out.println("Resending frames");
				for(i=0;i<nf;i++){	
					buf[i]=br.readLine();
					op.writeBytes(buf[i] + '\n');   
				}
			}
			System.out.println("Window size changed");		
			System.out.println("Remaining Window Size:"+sws);
			System.out.println("Continue.. press 1 or press 0");
			b=Integer.parseInt(br.readLine());      
		} while(b==1);   
	}
} 

receiver

import java.io.*;
import java.net.*; 
class SlidingWindowReciever{  	
	public static void main(String argv[]) throws Exception{   	
		String msg1;   
		String msg2="";
		String buf[]=new String[10];
		int nf=0,i;
		Socket s = new Socket("localhost", 8000);
		System.out.println("SLIDING WINDOW RECIEVER");
		while(true)	{    
			DataOutputStream op = new DataOutputStream(s.getOutputStream());   
			BufferedReader br = new BufferedReader(new    InputStreamReader (s.getInputStream()));
			nf = Integer.parseInt(br.readLine()); 
			System.out.println(nf+" Messages Waiting");  
			//op.writeBytes(msg1 + '\n');   
			for(i=0;i<nf;i++){
				msg1 = br.readLine();
				System.out.println("Message From Sender: " +msg1);
			}
			int ack=nf;
			op.writeBytes(""+ack + '\n');
			System.out.println("Acknowledgement for "+nf+" messages sent");
			//Thread.sleep(1000); 
		}
	}
}

-- Applet --

import java.applet.*;
import java.awt.*;
public class app extends Applet{
	String s;
	Image picture;  
	public void init() {
		s="WELCOME";
		picture = getImage(getDocumentBase(),"jerry.png"); 
	}
	public void paint(Graphics g) {
		Font f = new Font("TimesRoman", Font.PLAIN, 50);
		g.setFont(f);
		g.setColor(Color.RED);
		g.drawString(s,400,150);
		g.drawLine(20,20,20,250);
		g.setColor(Color.ORANGE);
		g.fillRect(20,20,200,30);
		g.setColor(Color.WHITE);
		g.fillRect(20,50,200,30); 
		g.setColor(Color.GREEN);
		g.fillRect(20,80,200,30);
		g.setColor(Color.BLUE);
		g.fillOval(110,50,30,30);
		g.drawImage(picture, 200,200, this);
	}
}



-- JDBC --

import java.io.*;
import java.sql.*;
import java.lang.*;

public class jdbc1{
	public static void main(String args[]) throws Exception{
		DataInputStream ds=new DataInputStream(System.in);
		System.out.println("Enter the  rollno.");
		int rollno=Integer.parseInt(ds.readLine());
		Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
		Connection con=DriverManager.getConnection("jdbc:odbc:ee","scott","tiger");
		Statement stmt=con.createStatement();
		ResultSet rs=stmt.executeQuery("Select * from student where ROLLNO= " +rollno);
		while(rs.next()){
			System.out.println("Rollno:"+rs.getString(1));
			System.out.println("Name:"+rs.getString(2));
			System.out.println("Marks:"+rs.getString(3));
		}
	}
}