EXP 1 - WAP to study load load distribution in distributed computing
Code :-
import java.util.Scanner;
class Main {
static void printLoad(int servers, int processes) {
int each = processes / servers;
int extra = processes % servers;
int total = 0;
for (int i = 0; i < servers; i++) {
if (extra-- > 0)
total = each + 1;
else
total = each;
System.out.println("Server " + (char)('A' + i) + " has " + total + " Processes");
}
}
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter the number of servers and processes: ");
int servers = sc.nextInt();
int processes = sc.nextInt();
while (true) {
printLoad(servers, processes);
System.out.print(
"1. Add Server\n" +
"2. Remove Server\n" +
"3. Add Processes\n" +
"4. Remove Processes\n" +
"5. Exit\n" +
"Enter your choice: "
);
switch (sc.nextInt()) {
case 1:
System.out.print("How many more servers?: ");
servers += sc.nextInt();
break;
case 2:
System.out.print("How many servers to remove?: ");
servers -= sc.nextInt();
break;
case 3:
System.out.print("How many more processes?: ");
processes += sc.nextInt();
break;
case 4:
System.out.print("How many processes to remove?: ");
processes -= sc.nextInt();
break;
case 5:
return;
}
}
}
}
EXP - 2
Aim - WAP to study bulley election algorithm
Code -
import java.io.*;
class BullyAlgo {
int cood, ch, crash;
int[] prc;
public void election(int n) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("\nThe Coordinator Has Crashed!");
int flag = 1;
while (flag == 1) {
crash = 0;
for (int i = 0; i < n; i++) {
if (prc[i] == 0) {
crash++;
}
}
if (crash == n) {
System.out.println("\n*** All Processes Are Crashed ***");
break;
} else {
System.out.println("\nEnter The Initiator");
int init = Integer.parseInt(br.readLine());
if ((init < 1) || (init > n) || (prc[init - 1] == 0)) {
System.out.println("\nInvalid Initiator");
continue;
}
for (int i1 = init - 1; i1 < n; i1++) {
System.out.println("Process " + (i1 + 1) + " Called For Election");
}
System.out.println("");
for (int i1 = init - 1; i1 < n; i1++) {
if (prc[i1] == 0) {
System.out.println("Process " + (i1 + 1) + " Is Dead");
} else {
System.out.println("Process " + (i1 + 1) + " Is Alive");
}
}
for (int i1 = n - 1; i1 >= 0; i1--) {
if (prc[i1] == 1) {
cood = (i1 + 1);
System.out.println("\n*** New Coordinator: Is " + cood + " ***");
flag = 0;
break;
}
}
}
}
}
public void Bully() throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter The Number Of Processes:");
int n = Integer.parseInt(br.readLine());
prc = new int[n];
crash = 0;
for (int i = 0; i < n; i++) {
prc[i] = 1; // Initially, all processes are alive
}
cood = n;
do {
System.out.println("\n\t1. Crash A Process");
System.out.println("\t2. Recover A Process");
System.out.println("\t3. Display New Coordinator");
System.out.println("\t4. Exit");
ch = Integer.parseInt(br.readLine());
switch (ch) {
case 1:
System.out.println("\nEnter A Process To Crash");
int cp = Integer.parseInt(br.readLine());
if ((cp > n) || (cp < 1)) {
System.out.println("Invalid Process! Enter A Valid Process");
} else if ((prc[cp - 1] == 1) && (cood != cp)) {
prc[cp - 1] = 0;
System.out.println("\nProcess " + cp + " Has Been Crashed");
} else if ((prc[cp - 1] == 1) && (cood == cp)) {
prc[cp - 1] = 0;
election(n);
} else {
System.out.println("\nProcess " + cp + " is Already Crashed");
}
break;
case 2:
System.out.println("\nCrashed Processes Are:\n");
for (int i = 0; i < n; i++) {
if (prc[i] == 0) {
System.out.println(i + 1);
crash++;
}
}
System.out.println("Enter The Process You Want To Recover");
int rp = Integer.parseInt(br.readLine());
if ((rp < 1) || (rp > n)) {
System.out.println("\nInvalid Process. Enter A Valid ID");
} else if ((prc[rp - 1] == 0) && (rp > cood)) {
prc[rp - 1] = 1;
System.out.println("\nProcess " + rp + " Has Recovered");
cood = rp;
System.out.println("\nProcess " + rp + " Is The New Coordinator");
} else if (crash == n) {
prc[rp - 1] = 1;
cood = rp;
System.out.println("\nProcess " + rp + " Is The New Coordinator");
crash--;
} else if (prc[rp - 1] == 0 && rp < cood) {
prc[rp - 1] = 1;
System.out.println("\nProcess " + rp + " Has Recovered");
} else {
System.out.println("\nProcess " + rp + " Is Not A Crashed Process");
}
break;
case 3:
System.out.println("\nCurrent Coordinator is " + cood);
break;
case 4:
System.exit(0);
break;
default:
System.out.println("\nInvalid Entry!");
break;
}
} while (ch != 4);
}
public static void main(String args[]) throws IOException {
BullyAlgo ob = new BullyAlgo();
ob.Bully();
}
}
EXP - 3
Aim - WAP to study RMI in Distributed Computing
Code :-
AddInterface.java :-
import java.rmi.*;
public interface AddInterface extends Remote {
public int sum(int n1, int n2) throws RemoteException;
}
Add.java
import java.rmi.*;
import java.rmi.server.*;
public class Add extends UnicastRemoteObject implements AddInterface {
int num1, num2;
public Add() throws RemoteException {
}
public int sum(int n1, int n2) throws RemoteException {
num1 = n1;
num2 = n2;
return num1 + num2;
}
}
AddServer.java
import java.rmi.Naming;
public class AddServer {
public static void main(String[] args) {
try {
// Bind the remote object to the RMI registry with the name "Add"
Naming.rebind("Add", new Add());
System.out.println("Server is connected and waiting for the client...");
} catch (Exception e) {
System.out.println("Server could not connect: " + e);
}
}
AddClient.java
import java.rmi.Naming;
public class AddClient {
public static void main(String[] args) {
try {
// Look up the remote object (Add) in the RMI registry
AddInterface ai = (AddInterface) Naming.lookup("//localhost/Add");
// Call the remote method 'sum' and print the result
System.out.println("The sum of 2 numbers is: " + ai.sum(10, 2));
} catch (Exception e) {
// Handle any exceptions
System.out.println("Client Exception: " + e);
}
}
}
EXP - 4
Aim - Develop a client server application which implements Name Server. Let the client like a web browser sends a request containing a hostname, then a piece of software such as name server resolver sends a request to the name server to obtain the IP address of a hostname.
Code -
import java.net.*;
import java.io.*;
import java.util.*;
public class DNS
{
public static void main(String[] args)
{
int n;
BufferedReader in = new BufferedReader(new
InputStreamReader(System.in)); do
{
System.out.println("\n Menu: \n 1. DNS 2. Reverse DNS 3. Exit \n");
System.out.println("\n Enter your choice");
n = Integer.parseInt(System.console().readLine());
if(n==1)
{
try
{
System.out.println("\n Enter Host Name ");
String hname=in.readLine();
InetAddress address;
address = InetAddress.getByName(hname);
System.out.println("Host Name: " +
address.getHostName()); System.out.println("IP: " +
address.getHostAddress());
}
catch(IOException ioe)
{
ioe.printStackTrace();
}
}
if(n==2)
{
try
{
System.out.println("\n Enter IP address");
String ipstr = in.readLine();
InetAddress ia = InetAddress.getByName(ipstr);
System.out.println("IP: "+ipstr);
System.out.println("Host Name: " +ia.getHostName());
}
catch(IOException ioe)
{
ioe.printStackTrace();
}
}
}while(!(n==3));
}}
EXP - 5
Aim - To develop a client server application this implements chat server
Code :-
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.IOException;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import java.awt.Gridlayout;
public class CCLogin implements ActionListener {
JFrame frame1;
JTextField tf;
JButton button;
JLabel heading, label;
public static void main(String[] args) {
new CCLogin();
}
public CCLogin() {
this.frame1 = new JFrame("Login Page");
this.tf = new JTextField(10);
this.button = new JButton("Login");
this.heading = new JLabel("Chat Server");
this.heading.setFont(new Font("Impact", Font.BOLD, 40));
this.label = new JLabel("Enter your Login Name");
this.label.setFont(new Font("Serif", Font.PLAIN, 24));
JPanel localJPanel = new JPanel();
this.button.addActionListener(this);
localJPanel.add(this.heading);
localJPanel.add(this.label);
localJPanel.add(this.tf);
localJPanel.add(this.button);
this.heading.setBounds(30, 20, 280, 50);
this.label.setBounds(20, 100, 250, 60);
this.tf.setBounds(50, 150, 150, 30);
this.button.setBounds(70, 190, 90, 30);
this.frame1.add(localJPanel);
localJPanel.setLayout(null);
this.frame1.setSize(300, 300);
this.frame1.setVisible(true);
this.frame1.setDefaultCloseOperation(3);
}
public void actionPerformed(ActionEvent paramActionEvent) {
String str = "";
try {
str = this.tf.getText();
this.frame1.dispose();
Client1 c1 = new Client1(str);
c1.main(null);
} catch (Exception localIOException) {
// Handle exception
localIOException.printStackTrace();
}
}
}
EXP -6
Aim - WAP to study Berkeley Clock synchronization algorithm
Code -
import java.io.*;
import java.util.*;
public class Berkley {
// Function to calculate the time difference between Time Server and Nodes
float diff(int h, int m, int s, int nh, int nm, int ns) {
int dh = h - nh;
int dm = m - nm;
int ds = s - ns;
int diff = (dh * 60 * 60) + (dm * 60) + ds;
return diff;
}
// Function to calculate the average of all time differences
float average(float diff[], int n) {
int sum = 0;
for (int i = 0; i < n; i++) {
sum += diff[i];
}
float average = (float) sum / (n + 1);
System.out.println("The average of all time differences is " + average);
return average;
}
// Function to synchronize the clocks based on the average time difference
void sync(float diff[], int n, int h, int m, int s, int nh[], int nm[], int ns[], float average)
{
for (int i = 0; i < n; i++) {
diff[i] += average;
int dh = (int) diff[i] / (60 * 60);
diff[i] %= (60 * 60);
int dm = (int) diff[i] / 60;
diff[i] %= 60;
int ds = (int) diff[i];
nh[i] += dh;
if (nh[i] > 23) {
nh[i] %= 24;
}
nm[i] += dm;
if (nm[i] > 59) {
nh[i]++;
nm[i] %= 60;
}
ns[i] += ds;
if (ns[i] > 59) {
nm[i]++;
ns[i] %= 60;
}
if (ns[i] < 0) {
nm[i]--;
ns[i] += 60;
}
}
// Adjust Time Server clock
h += (int) (average / (60 * 60));
if (h > 23) {
h %= 24;
}
m += (int) (average / (60 * 60));
if (m > 59) {
h++;
m %= 60;
}
s += (int) (average % (60 * 60));
if (s > 59) {
m++;
s %= 60;
}
if (s < 0) {
m--;
s += 60;
}
// Print synchronized clocks
System.out.println("The synchronized clocks are:");
System.out.println("Time Server -> " + h + ":" + m + ":" + s);
for (int i = 0; i < n; i++) {
System.out.println("Node " + (i + 1) + " -> " + nh[i] + ":" + nm[i] + ":" + ns[i]);
}
}
public static void main(String[] args) throws IOException {
Berkley b = new Berkley();
Date date = new Date();
BufferedReader obj = new BufferedReader(new
InputStreamReader(System.in));
System.out.println("Enter number of nodes:");
int n = Integer.parseInt(obj.readLine());
int h = date.getHours();
int m = date.getMinutes();
int s = date.getSeconds();
int nh[] = new int[n];
int nm[] = new int[n];
int ns[] = new int[n];
// Input times for each node
for (int i = 0; i < n; i++) {
System.out.println("Enter time for node " + (i + 1));
System.out.print("Hours: ");
nh[i] = Integer.parseInt(obj.readLine());
System.out.print("Minutes: ");
nm[i] = Integer.parseInt(obj.readLine());
System.out.print("Seconds: ");
ns[i] = Integer.parseInt(obj.readLine());
}
// Send the Time Server's time to the nodes and calculate the differences
System.out.println("Time Server sent time " + h + ":" + m + ":" + s + " to nodes.");
float diff[] = new float[n];
for (int i = 0; i < n; i++) {
diff[i] = b.diff(h, m, s, nh[i], nm[i], ns[i]);
System.out.println("Node " + (i + 1) + " sent time difference of " + (int) diff[i] +
" to Time Server.");
}
// Calculate the average time difference and synchronize clocks
float average = b.average(diff, n);
b.sync(diff, n, h, m, s, nh, nm, ns, average);
}
}
EXP - 7
Aim - WAP to demonstrate the implementation of a multi-threaded application using
Java.
Code :-
class Threads extends Thread {
// Constructor for the Threads class
Threads() {
super("User Threads");
System.out.println("User thread is created: " + this);
start(); // Start the thread
}
// The run() method that defines the task of the child thread
public void run() {
try {
for (int i = 1; i <= 7; i++) {
System.out.println("Printing the count of Child Thread: " + i);
Thread.sleep(800); // Sleep for 800 milliseconds
}
} catch (InterruptedException e) {
System.out.println("User thread Interrupted");
}
System.out.println("Child thread run is over");
}
}
public class Multithreading {
public static void main(String args[]) {
Threads th = new Threads(); // Create and start the child thread
try {
// The parent thread will continue to run as long as the child thread is alive
while (th.isAlive()) {
System.out.println("Parent thread will run till the Child thread is alive");
Thread.sleep(1500); // Parent thread sleeps for 1500 milliseconds
}
} catch (InterruptedException e) {
System.out.println("Parent thread interrupted");
}
System.out.println("Parent thread's run is over");
}
}
