DSprac3

RMI EXECUTION(3 TERMINAL OPEN)

notepad type inside folder create

path="c-pf-java-jdk-bin  vala  path copy "
1) i)>javac *.java
   iii)>rmic implfile
   iv)>java serverfile
2)ii)>start rmiregistry

3)v)>java clientfile


TCP
1. tcpServerPrime.java
import java.net.*; import java.io.*;
class tcpServerPrime
{
public static void main(String args[])
{
try
{
ServerSocket ss = new ServerSocket(8001); System.out.println("Server Started..............."); Socket s = ss.accept();
DataInputStream in = new DataInputStream(s.getInputStream()); int x= in.readInt(); DataOutputStream otc = new DataOutputStream(s.getOutputStream()); int y = x/2; if(x ==1 || x ==2 || x ==3)
{
otc.writeUTF(x + "is Prime"); System.exit(0);
}
for(int i=2; i<=y; i++)
{
if(x%i != 0)
{
}
else
{
}
}
}
otc.writeUTF(x + " is Prime");
otc.writeUTF(x + " is not Prime");
catch(Exception e)
{
System.out.println(e.toString());
}
}
}

2. tcpClientPrime.java
import java.net.*; import java.io.*;
class tcpClientPrime
{
public static void main(String args[])
{
try
{
Socket cs = new Socket("LocalHost",8001); BufferedReader infu = new BufferedReader(new
InputStreamReader(System.in));
System.out.println("Enter a number : "); int a = Integer.parseInt(infu.readLine()); DataOutputStream out = new
DataOutputStream(cs.getOutputStream());
out.writeInt(a); DataInputStream in = new
DataInputStream(cs.getInputStream()); System.out.println(in.readUTF()); cs.close();
}
catch(Exception e)
{
System.out.println(e.toString());
}
}
}

CHAT
1. ChatServer.java
import java.net.*; import java.io.*;
class ChatServer
{
public static void main(String args[])
{
try
{
ServerSocket ss = new ServerSocket(8000); System.out.println("Waiting for client to connect.."); Socket s = ss.accept();
BufferedReader br = new BufferedReader(new
InputStreamReader(System.in));
DataOutputStream out = new DataOutputStream(s.getOutputStream()); DataInputStream in = new DataInputStream(s.getInputStream()); String receive, send; while((receive = in.readLine()) != null)
{
if(receive.equals("STOP")) break;
System.out.println("Client Says : "+receive); System.out.print("Server Says : ");
send = br.readLine(); out.writeBytes(send+"\n");
}
br.close();
in.close();
out.close();

s.close();
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
2. ChatClient.java
import java.net.*; import java.io.*;
class ChatClient
{
public static void main(String args[])
{
try
{
Socket s = new Socket("Localhost",8000); BufferedReader br = new BufferedReader(new
InputStreamReader(System.in));
DataOutputStream out = new DataOutputStream(s.getOutputStream()); DataInputStream in = new DataInputStream(s.getInputStream()); String msg; System.out.println("To stop chatting with server type
STOP"); System.out.print("Client Says: "); while((msg = br.readLine()) != null)
{
out.writeBytes(msg+"\n"); if(msg.equals("STOP"))
break;
System.out.println("Server Says : "+in.readLine()); System.out.print("Client Says : ");
}
br.close();
in.close();
out.close();
s.close();
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
UDP
1. udpServerEO.java
/*Program which finds entered number is even or odd */ import java.io.*;
import java.net.*;
public class udpServerEO
{
public static void main(String args[])
{
try
{
DatagramSocket ds = new DatagramSocket(2000); byte b[] = new byte[1024];
DatagramPacket dp = new DatagramPacket(b,b.length); ds.receive(dp);
String str = new String(dp.getData(),0,dp.getLength()); System.out.println(str);
int a= Integer.parseInt(str); String s= new String();
if (a%2 == 0)
s = "Number is even";
else
s = "Number is odd";
byte b1[] = new byte[1024]; b1 = s.getBytes(); DatagramPacket dp1 = new
DatagramPacket(b1,b1.length,InetAddress.getLocalHost(),1000);
ds.send(dp1);
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
2. udpClientEO.java
/*Program which finds entered number is even or odd*/
import java.io.*; import java.net.*;
public class udpClientEO
{
public static void main(String args[])
{
try

{
DatagramSocket ds = new DatagramSocket(1000); BufferedReader br = new BufferedReader(new
InputStreamReader(System.in));
System.out.println("Enter a number : "); String num = br.readLine();
byte b[] = new byte[1024]; b=num.getBytes(); DatagramPacket dp = new
DatagramPacket(b,b.length,InetAddress.getLocalHost(),2000);
ds.send(dp);
byte b1[] = new byte[1024]; DatagramPacket dp1 = new
DatagramPacket(b1,b1.length); ds.receive(dp1);
String str = new String(dp1.getData(),0,dp1.getLength()); System.out.println(str);
}
catch(Exception e)
{
e.printStackTrace();
}
}
}

1. udpServerFact.java
/*Program which calculate factorial of a number*/ import java.io.*;
import java.net.*;
public class udpServerFact
{
public static void main(String args[])
{
try
{
DatagramSocket ds = new DatagramSocket(2000); byte b[] = new byte[1024];
DatagramPacket dp = new DatagramPacket(b,b.length); ds.receive(dp);
String str = new String(dp.getData(),0,dp.getLength()); System.out.println(str);
int a= Integer.parseInt(str); int f = 1, i;
String s= new String(); for(i=1;i<=a;i++)
{
f=f*i;
}
s=Integer.toString(f);
String str1 = "The Factorial of " + str + " is : " + f; byte b1[] = new byte[1024]; b1 = str1.getBytes(); DatagramPacket dp1 = new
DatagramPacket(b1,b1.length,InetAddress.getLocalHost(),1000);
ds.send(dp1);
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
2. udpClientFact.java
/*Program which calculate factorial of a number*/ import java.io.*;

import java.net.*;
public class udpClientFact
{
public static void main(String args[])
{
try
{
DatagramSocket ds = new DatagramSocket(1000); BufferedReader br = new BufferedReader(new
InputStreamReader(System.in));
System.out.println("Enter a number : "); String num = br.readLine();
byte b[] = new byte[1024]; b=num.getBytes(); DatagramPacket dp = new
DatagramPacket(b,b.length,InetAddress.getLocalHost(),2000);
ds.send(dp);
byte b1[] = new byte[1024];
DatagramPacket dp1 = new DatagramPacket(b1,b1.length); ds.receive(dp1);
String str = new String(dp1.getData(),0,dp1.getLength()); System.out.println(str);
}
catch(Exception e)
{
e.printStackTrace();
}
}
}

RMI
1
1. InterDate.java
import java.rmi.*;
public interface InterDate extends Remote
{
public String display() throws Exception;
}
2. ServerDate.java
import java.rmi.*; import java.rmi.server.*; import java.util.*;
public class ServerDate extends UnicastRemoteObject implements InterDate {
public ServerDate() throws Exception
{
}
public String display() throws Exception
{
String str = "";
Date d = new Date(); str = d.toString(); return str;
}
public static void main(String args[]) throws Exception {
ServerDate s1 = new ServerDate(); Naming.bind("DS",s1); System.out.println("Object registered.....");
}
}
3. ClientDate.java
import java.rmi.*; import java.io.*;

public class ClientDate
{
public static void main(String args[]) throws Exception {
String s1;
InterDate h1 = (InterDate)Naming.lookup("DS"); s1 = h1.display();
System.out.println(s1);
}
}

1STEP= javac file name.java(3file)
2step= rmic server
3step= rmiregistry

java server

java client
2)
1. InterConvert.java
import java.rmi.*;
public interface InterConvert extends Remote
{
public String convertDigit(String no) throws Exception;
}
2. ServerConvert.java
import java.rmi.*; import java.rmi.server.*;
public class ServerConvert extends UnicastRemoteObject implements InterConvert {
public ServerConvert() throws Exception
{
}
public String convertDigit(String no) throws Exception
{
String str = "";
for(int i = 0; i < no.length(); i++)
{
int p = no.charAt(i); if( p == 48)
{
str += "zero ";
}
if( p == 49)
{
str += "one ";
}
if( p == 50)
{
str += "two ";
}
if( p == 51)
{
str += "three ";
}
if( p == 52)
{
str += "four ";

}
if( p == 53)
{
str += "five ";
}
if( p == 54)
{
str += "six ";
}
if( p == 55)
{
str += "seven ";
}
if( p == 56)
{
str += "eight ";
}
if( p == 57)
{
str += "nine ";
}
}
return str;
}
public static void main(String args[]) throws Exception {
ServerConvert s1 = new ServerConvert(); Naming.bind("Wrd",s1); System.out.println("Object registered....");
}
}
3. ClientConvert.java
import java.rmi.*; import java.io.*;
public class ClientConvert
{
public static void main(String args[]) throws Exception {
InterConvert h1 = (InterConvert)Naming.lookup("Wrd"); BufferedReader br = new BufferedReader(new
InputStreamReader(System.in));
System.out.println("Enter a number : \t"); String no = br.readLine();
String ans = h1.convertDigit(no);
System.out.println("The word representation of the entered digit is : " +ans);
}
}

RPC
1. RPCServer.java
import java.util.*; import java.net.*;
class RPCServer
{
DatagramSocket ds;
DatagramPacket dp;
String str,methodName,result; int val1,val2;
RPCServer()
{
try
{
ds=new DatagramSocket(1200); byte b[]=new byte[4096];
while(true)
{
dp=new DatagramPacket(b,b.length); ds.receive(dp);
str=new String(dp.getData(),0,dp.getLength());
if(str.equalsIgnoreCase("q"))
{
}
else
{
System.exit(1);
StringTokenizer st = new StringTokenizer(str," "); int i=0;
while(st.hasMoreTokens())
{
String token=st.nextToken(); methodName=token;
val1 = Integer.parseInt(st.nextToken()); val2 = Integer.parseInt(st.nextToken());
}

}
System.out.println(str);
InetAddress ia = InetAddress.getLocalHost();
if(methodName.equalsIgnoreCase("add"))
{
result= "" + add(val1,val2);
}
else if(methodName.equalsIgnoreCase("sub"))
{
result= "" + sub(val1,val2);
}
else if(methodName.equalsIgnoreCase("mul"))
{
result= "" + mul(val1,val2);
}
else if(methodName.equalsIgnoreCase("div"))
{
result= "" + div(val1,val2);
}
byte b1[]=result.getBytes();
DatagramSocket ds1 = new DatagramSocket(); DatagramPacket dp1 = new
DatagramPacket(b1,b1.length,InetAddress.getLocalHost(), 1300);
System.out.println("result : "+result+"\n"); ds1.send(dp1);
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
public int add(int val1, int val2)
{
return val1+val2;
}
public int sub(int val3, int val4)
{
return val3-val4;
}
public int mul(int val3, int val4)
{
return val3*val4;
}
public int div(int val3, int val4)
{
return val3/val4;
}

public static void main(String[] args)
{
new RPCServer();
}
}
2. RPCClient.java
import java.io.*; import java.net.*;
class RPCClient
{
RPCClient()
{
4\n");
try
{
InetAddress ia = InetAddress.getLocalHost(); DatagramSocket ds = new DatagramSocket(); DatagramSocket ds1 = new DatagramSocket(1300); System.out.println("\nRPC Client\n");
System.out.println("Enter method name and parameter like add 3
while (true)
{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String str = br.readLine(); byte b[] = str.getBytes(); DatagramPacket dp = new
DatagramPacket(b,b.length,ia,1200);
ds.send(dp);
dp = new DatagramPacket(b,b.length); ds1.receive(dp);
String s = new String(dp.getData(),0,dp.getLength()); System.out.println("\nResult = " + s + "\n");
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
public static void main(String[] args)
{
new RPCClient();
}
}

1. RPCNumServer.java
import java.util.*; import java.net.*; import java.io.*; class RPCNumServer
{
DatagramSocket ds;

DatagramPacket dp;
String str,methodName,result; int val;
RPCNumServer()
{
try
{
ds=new DatagramSocket(1200); byte b[]=new byte[4096]; while(true)
{
dp=new DatagramPacket(b,b.length); ds.receive(dp);
str=new String(dp.getData(),0,dp.getLength()); if(str.equalsIgnoreCase("q")) {
System.exit(1);
}
else
{
StringTokenizer st = new StringTokenizer(str," "); int i=0;
while(st.hasMoreTokens())
{
String token=st.nextToken(); methodName=token;
val = Integer.parseInt(st.nextToken());
}
}
System.out.println(str);
InetAddress ia = InetAddress.getLocalHost(); if(methodName.equalsIgnoreCase("square"))
{
result= "" + square(val);
}
else if(methodName.equalsIgnoreCase("squareroot"))
{
result= "" + squareroot(val);
}
else if(methodName.equalsIgnoreCase("cube"))
{
result= "" + cube(val);
}
else if(methodName.equalsIgnoreCase("cuberoot"))
{
result= "" + cuberoot(val);
}
byte b1[]=result.getBytes();
DatagramSocket ds1 = new DatagramSocket();

DatagramPacket dp1 = new DatagramPacket(b1,b1.length,InetAddress.getLocalHost(), 1300);
System.out.println("result : "+result+"\n"); ds1.send(dp1);
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
public double square(int a) throws Exception
{
double ans; ans = a*a; return ans;
}
public double squareroot(int a) throws Exception
{
double ans;
ans = Math.sqrt(a); return ans;
}
public double cube(int a) throws Exception
{
double ans; ans = a*a*a; return ans;
}
public double cuberoot(int a) throws Exception
{
double ans;
ans = Math.cbrt(a); return ans;
}
public static void main(String[] args)
{
new RPCNumServer();
}
}
2. RPCNumClient.java
import java.io.*; import java.net.*; class RPCNumClient
{
RPCNumClient()
{
try
{

InetAddress ia = InetAddress.getLocalHost(); DatagramSocket ds = new DatagramSocket(); DatagramSocket ds1 = new DatagramSocket(1300); System.out.println("\nRPC Client\n");
System.out.println("1. Square of the number - square\n2. Square root of the number - squareroot\n3. Cube of the number - cube\n4. Cube root of the number - cuberoot");
System.out.println("Enter method name and the number\n"); while (true)
{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String str = br.readLine(); byte b[] = str.getBytes(); DatagramPacket dp = new
DatagramPacket(b,b.length,ia,1200);
ds.send(dp);
dp = new DatagramPacket(b,b.length); ds1.receive(dp);
String s = new String(dp.getData(),0,dp.getLength()); System.out.println("\nResult = " + s + "\n");
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
public static void main(String[] args)
{
new RPCNumClient();
}
}

SQL WEBSERVICES
Code Spec
package webservice;
import java.sql.*;
import javax.jws.WebMethod; import javax.jws.WebParam; import javax.jws.WebService; import javax.ejb.Stateless;
@WebService() @Stateless()
public class BookWS {
/**
* Web service operation
*/
@WebMethod(operationName = "getBookDetails") public String getBookDetails(@WebParam(name = "isbn") String isbn) {
//TODO write your implementation code here: Connection dbcon = null;
Statement stmt = null; ResultSet rs = null; String query = null; try
{
Class.forName("com.mysql.jdbc.Driver").newInstance();
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dbcon =
DriverManager.getConnection("jdbc:mysql://localhost/bookshop","root","123"); stmt = dbcon.createStatement();
query = "select * from books where isbn = '" +isbn+ "'"; rs = stmt.executeQuery(query); rs.next();
String bookDetails = "<h1>The name of the book is <b>"
+rs.getString("bookname") + "</b> and its cost is <b>" +rs.getString("bookprice") + "</b></h1>.";
return bookDetails;
}
catch(Exception e)
{
System.out.println("Sorry failed to connect to the database.." + e.getMessage());
}
return null;
}
}

MUTUAL TOKEN
1. TokenServer.java
import java.io.*; import java.net.*;
public class TokenServer
{
public static void main(String agrs[])throws Exception {
while(true)
{
Server sr=new Server(); sr.recPort(8000); sr.recData();
}
}
}
class Server
{
boolean hasToken=false; boolean sendData=false; int recport;
void recPort(int recport)
{
this.recport=recport;
}
void recData()throws Exception
{
byte buff[]=new byte[256];
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DatagramSocket ds; DatagramPacket dp; String str;
ds=new DatagramSocket(recport);
dp=new DatagramPacket(buff,buff.length); ds.receive(dp);
ds.close();
str=new String(dp.getData(),0,dp.getLength()); System.out.println("The message is "+str);
}
}
2. TokenClient1.java
import java.io.*; import java.net.*;
public class TokenClient1
{
public static void main(String arg[]) throws Exception
{
InetAddress lclhost; BufferedReader br; String str=""; TokenClient12 tkcl,tkser; boolean hasToken; boolean setSendData;
while(true)
{
lclhost=InetAddress.getLocalHost(); tkcl = new TokenClient12(lclhost); tkser = new TokenClient12(lclhost); tkcl.setSendPort(9004); tkcl.setRecPort(8002); lclhost=InetAddress.getLocalHost(); tkser.setSendPort(9000);
if(tkcl.hasToken == true)
{
YES/NO");
System.out.println("Do you want to enter the Data -->
br=new BufferedReader(new InputStreamReader(System.in)); str=br.readLine();
if(str.equalsIgnoreCase("yes"))
{
System.out.println("ready to send"); tkser.setSendData = true; tkser.sendData();
tkser.setSendData = false;
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}
else if(str.equalsIgnoreCase("no"))
{
}
}
else
{
tkcl.sendData(); tkcl.recData();
System.out.println("ENTERING RECEIVING MODE..."); tkcl.recData();
}
}
}
}
class TokenClient12
{
InetAddress lclhost; int sendport,recport;
boolean hasToken = true; boolean setSendData = false; TokenClient12 tkcl,tkser;
TokenClient12(InetAddress lclhost)
{
this.lclhost = lclhost;
}
void setSendPort(int sendport)
{
this.sendport = sendport;
}
void setRecPort(int recport)
{
this.recport = recport;
}
void sendData() throws Exception
{
BufferedReader br; String str="Token"; DatagramSocket ds; DatagramPacket dp;
if(setSendData == true)
{
System.out.println("sending "); System.out.println("Enter the Data");
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Distributed Systems – Practical Manual – 2018-2019
br=new BufferedReader(new InputStreamReader(System.in)); str = "ClientOne....." + br.readLine(); System.out.println("now sending");
}
ds = new DatagramSocket(sendport);
dp = new DatagramPacket(str.getBytes(),str.length(),lclhost,sendport-1000); ds.send(dp);
ds.close(); setSendData = false; hasToken = false;
}
void recData()throws Exception
{
String msgstr;
byte buffer[] = new byte[256]; DatagramSocket ds; DatagramPacket dp;
ds = new DatagramSocket(recport);
dp = new DatagramPacket(buffer,buffer.length); ds.receive(dp);
ds.close();
msgstr = new String(dp.getData(),0,dp.getLength()); System.out.println("The data is "+msgstr);
if(msgstr.equals("Token"))
{
hasToken = true;
}
}
}
3. TokenClient2.java
import java.io.*; import java.net.*;
public class TokenClient2
{
static boolean setSendData ; static boolean hasToken ;
public static void main(String arg[]) throws Exception
{
InetAddress lclhost; BufferedReader br; String str1; TokenClient21 tkcl; TokenClient21 ser;
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while(true)
{
lclhost=InetAddress.getLocalHost(); tkcl = new TokenClient21(lclhost); tkcl.setRecPort(8004); tkcl.setSendPort(9002); lclhost=InetAddress.getLocalHost(); ser = new TokenClient21(lclhost); ser.setSendPort(9000);
if(hasToken == true)
{
YES/NO");
System.out.println("Do you want to enter the Data -->
br=new BufferedReader(new InputStreamReader(System.in)); str1=br.readLine();
if(str1.equalsIgnoreCase("yes"))
{
ser.setSendData = true; ser.sendData();
}
else if(str1.equalsIgnoreCase("no"))
{
}
}
else
{
tkcl.sendData(); hasToken=false;
System.out.println("entering recieving mode"); tkcl.recData();
hasToken=true;
}
}
}
}
class TokenClient21
{
InetAddress lclhost; int sendport,recport;
boolean setSendData = false; boolean hasToken = false; TokenClient21 tkcl; TokenClient21 ser;
TokenClient21(InetAddress lclhost)
{
this.lclhost = lclhost;
}
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void setSendPort(int sendport)
{
this.sendport = sendport;
}
void setRecPort(int recport)
{
this.recport = recport;
}
void sendData() throws Exception
{
BufferedReader br; String str="Token"; DatagramSocket ds; DatagramPacket dp;
if(setSendData == true)
{
System.out.println("Enter the Data");
br=new BufferedReader(new InputStreamReader(System.in)); str = "ClientTwo....." + br.readLine();
}
ds = new DatagramSocket(sendport);
dp = new DatagramPacket(str.getBytes(),str.length(),lclhost,sendport-1000); ds.send(dp);
ds.close(); System.out.println("Data Sent"); setSendData = false;
hasToken = false;
}
void recData()throws Exception
{
String msgstr;
byte buffer[] = new byte[256]; DatagramSocket ds;
DatagramPacket dp; ds = new DatagramSocket(recport); dp = new DatagramPacket(buffer,buffer.length); ds.receive(dp);
ds.close(); msgstr = new
String(dp.getData(),0,dp.getLength()); System.out.println("The data is "+msgstr); if(msgstr.equals("Token")) {
hasToken = true;
}
}
}


CLOCK SYCHRONIZATION
1. SCServer.java
import java.io.*; import java.net.*; import java.sql.*;
public class SCServer
{
public static void main(String args[])throws Exception {
InetAddress lclhost; lclhost=InetAddress.getLocalHost();
long maxtime,skewtime,datatime; String maxtimestr,skewtimestr; BufferedReader br;
ClntServer ser=new ClntServer(lclhost);
System.out.println("Enter the maximum time"); br = new BufferedReader(new
InputStreamReader(System.in)); maxtimestr=br.readLine();
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System.out.println("Enter the maximum skew time"); br = new BufferedReader(new
InputStreamReader(System.in)); skewtimestr=br.readLine();
maxtime=Long.parseLong(maxtimestr); skewtime=Long.parseLong(skewtimestr);
while(true)
{
}
}
}
datatime = System.currentTimeMillis(); long G = datatime-maxtime-skewtime; System.out.println("G ="+G); ser.setTimeStamp(new Timestamp(G)); ser.recPort(8001);
ser.recData();
class ClntServer
{
InetAddress lclhost; int recport; Timestamp obtmp;
ClntServer(InetAddress lclhost)
{
this.lclhost = lclhost;
}
void recPort(int recport)
{
this.recport = recport;
}
void setTimeStamp(Timestamp obtmp)
{
this.obtmp = obtmp;
}
void recData()throws Exception
{
String msgstr=""; DatagramSocket ds; DatagramPacket dp; BufferedReader br;
byte buf[] = new byte[256];
ds = new DatagramSocket(recport);
dp = new DatagramPacket(buf,buf.length);
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ds.receive(dp); ds.close();
msgstr = new String(dp.getData(),0,dp.getLength()); System.out.println(msgstr);
Timestamp obtmp = new Timestamp(Long.parseLong(msgstr)); if(this.obtmp.before(obtmp) == true)
{
}
else
{
}
}
}
System.out.println("The Message is accepted");
System.out.println("The Message is rejected");
2. SCClient.java
import java.io.*; import java.net.*;
public class SCClient
{
public static void main(String args[])throws Exception {
InetAddress lclhost; lclhost=InetAddress.getLocalHost();
while(true)
{
}
}
}
Client cntl=new Client(lclhost); cntl.sendPort(9001); cntl.sendData();
class Client
{
InetAddress lclhost; int senport;
Client(InetAddress lclhost)
{
this.lclhost=lclhost;
}
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void sendPort(int senport)
{
this.senport=senport;
}
void sendData()throws Exception
{
DatagramPacket dp; DatagramSocket ds; BufferedReader br;
br=new BufferedReader(new InputStreamReader(System.in)); System.out.println("Enter the data"); String str=br.readLine();
ds = new DatagramSocket(senport);
dp = new DatagramPacket(str.getBytes(),str.length(),lclhost,senport-1000); ds.send(dp);
ds.close();
}
}

Write a program to implement two phase commit protocol.

Algorithm Used:
A) Actions by the coordinator:
Write START_2PC to local log;
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Multicast VOTE_REQUEST to all participants; While not all votes have been collected {
Wait for any incoming vote; If timeout
{
Write GLOBAL_ABORT to local log; Multicast GLOBAL_ABORT to all participants; Exit;
}
record vote;
}
If all participant sent VOTE_COMMIT and coordinator votes COMMIT
{
}
else
{
}
Write GLOBAL_COMMIT to local log; Multicast GLOBAL_COMMIT to all participants;
Write GLOBAL_ABORT to local log; Multicast GLOBAL_ABORT to all participants;
B) Actions by participants:
Write INIT to local log;
Wait for VOTE_REQUEST from coordinator; If timeout
{
write VOTE_ABORT to local log; exit;
}
if participant vote COMMIT
{
write VOTE_COMMIT to local log; send VOTE_COMMIT to coordinator; wait for DECISION from coordinator; if timeout
{
multicast DECISION_REQUEST to other participants; wait until DECISION is received;/*remain blocked*/ write DECISION to local log;
}
}
else
{
if DECISION= = GLOBAL_COMMIT
write GLOBAL_COMMIT to local log; else if DECISION= = GLOBAL_ABORT
write GLOBAL_ABORT to local log;
write VOTE_ABORT to local log;
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send VOTE_ABORT to coordinator;
}
C) Action for handling decision request:
While true
{
}
Code:
wait until any incoming DECISION_REQUEST is received;/*remain blocked*/ read most recently recorded STATES from the local log;
if STATE= = GLOBAL_COMMIT
send GLOBAL_COMMIT to requesting participants; else if STATE= =INIT or STATE= = GLOBAL_ABORT send
GLOBAL_ABORT to requesting participants;
else
skip;/* participant remains blocked.*/
1. Server.java
import java.io.*; import java.net.*; import java.util.*;
public class Server
{
boolean closed=false,inputFromAll=false; List<clientThread> t;
List<String> data;
Server()
{
t = new ArrayList<clientThread>(); data= new ArrayList<String>();
}
public static void main(String args[])
{
Socket clientSocket = null; ServerSocket serverSocket = null; int port_number=1111;
Server ser=new Server(); try
{
serverSocket = new ServerSocket(port_number);
}
catch (IOException e)
{
System.out.println(e);
}
while(!ser.closed)
{
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}
try
{
try
{
}
clientSocket = serverSocket.accept();
clientThread th=new clientThread(ser,clientSocket); (ser.t).add(th);
System.out.println("\nNow Total clients are : "+(ser.t).size()); (ser.data).add("NOT_SENT");
th.start();
catch (IOException e)
{
}
serverSocket.close();
}
catch(Exception e1)
{
}
}
}
class clientThread extends Thread
{
DataInputStream is = null; String line;
String destClient=""; String name; PrintStream os = null;
Socket clientSocket = null; String clientIdentity; Server ser;
public clientThread(Server ser,Socket clientSocket)
{
this.clientSocket=clientSocket; this.ser=ser;
}
public void run()
{
try
{
is = new DataInputStream(clientSocket.getInputStream()); os = new PrintStream(clientSocket.getOutputStream()); os.println("Enter your name."); name = is.readLine(); clientIdentity=name;
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os.println("Welcome "+name+" to this 2 Phase Application.\nYou will receive a vote Request now...");
os.println("VOTE_REQUEST\nPlease enter COMMIT or ABORT to
proceed : ");
for(int i=0; i<(ser.t).size(); i++)
{
if((ser.t).get(i)!=this)
{
((ser.t).get(i)).os.println("---A new user
"+name+" entered the Appilcation---");
}
}
while (true)
{
line = is.readLine(); if(line.equalsIgnoreCase("ABORT"))
{
System.out.println("\nFrom '"+clientIdentity+"' :
ABORT\n\nSince aborted we will not wait for inputs from other clients.");
System.out.println("\nAborted....");
for(int i=0; i<(ser.t).size(); i++)
{
((ser.t).get(i)).os.println("GLOBAL_ABORT");
((ser.t).get(i)).os.close();
((ser.t).get(i)).is.close();
}
break;
}
if(line.equalsIgnoreCase("COMMIT"))
{
COMMIT");
System.out.println("\nFrom '"+clientIdentity+"' :
if((ser.t).contains(this))
{
(ser.data).set((ser.t).indexOf(this), "COMMIT"); for(int j=0;j<(ser.data).size();j++) {
if(!(((ser.data).get(j)).equalsIgnoreCase("NOT_SENT")))
{
}
else
{
ser.inputFromAll=true; continue;
ser.inputFromAll=false; System.out.println("\nWaiting for inputs from other clients.");
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break;
}
}
if(ser.inputFromAll)
{
System.out.println("\n\nCommited....");
for(int i=0; i<(ser.t).size(); i++)
{
((ser.t).get(i)).os.println("GLOBAL_COMMIT");
}
}//if t.contains
}//commit
}//while
ser.closed=true; clientSocket.close();
}
break;
((ser.t).get(i)).os.close();
((ser.t).get(i)).is.close();
}
catch(IOException e)
{
};
}
}
2. Client.java
import java.io.*; import java.net.*;
public class Client implements Runnable
{
static Socket clientSocket = null; static PrintStream os = null; static DataInputStream is = null;
static BufferedReader inputLine = null; static boolean closed = false;
public static void main(String[] args)
{
int port_number=1111; String host="localhost"; try
{
clientSocket = new Socket(host, port_number); inputLine = new BufferedReader(new
InputStreamReader(System.in));
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os = new PrintStream(clientSocket.getOutputStream());
is = new DataInputStream(clientSocket.getInputStream());
}
catch (Exception e)
{
System.out.println("Exception occurred : "+e.getMessage());
}
if (clientSocket != null && os != null && is != null)
{
try
{
new Thread(new Client()).start();
while (!closed)
{
os.println(inputLine.readLine());
}
os.close();
is.close();
clientSocket.close();
}
catch (IOException e)
{
System.err.println("IOException: " + e);
}
}
}
public void run()
{
String responseLine;
try
{
while ((responseLine = is.readLine()) != null)
{
System.out.println("\n"+responseLine);
if
(responseLine.equalsIgnoreCase("GLOBAL_COMMIT")==true ||
responseLine.equalsIgnoreCase("GLOBAL_ABORT")==true )
{
break;
}
}
closed=true;
}
catch (IOException e)
{
System.err.println("IOException: " + e);
}
}
}

O/P- JAVA SERVER
JAVA CLIENT(3TIMES)


RPC EXECUTION

JAVAC CLIENT
JAVA CLIENT
JAVA RPCServer
1)
TCP(Transmission Control Protocol)

Package used for Socket Programming Using  TCP / UDP


import java.io.*;
import java.net.*;



Connection Establishment Code.
Server:
try
        {
            int port = 8888;
            ServerSocket ss= new ServerSocket(port);
            System.out.println("Waiting for Client");
            Socket s = ss.accept();

        }
        catch (Exception e)
        {
            System.out.println("Error :" + e);
        }

Client
try
        {
            int port = 8888;
            InetAddress addr = InetAddress.getLocalHost();
            Socket s = new Socket(addr, port);
            System.out.println("Connection is established");


        }
        catch (Exception e)
        {
            System.out.println("Error :" + e);
        }




User Input In TCP/UDP(BufferedReader with System.in):


BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
            System.out.println("Enter The Number :");
            String req = br.readLine();


Send Data to Socket In TCP

PrintWriter pw = new PrintWriter(new OutputStreamWriter(s.getOutputStream()));
            pw.println(str);
            pw.flush();


Receive Data from Socket in TCP(BufferedReader with getInputStream()).

BufferedReader br = new BufferedReader(new InputStreamReader(s.getInputStream()));
            String str = br.readLine();
            System.out.println("Request From The Client :" + str);


UDP(User Datagram Protocol)
DatagramSocket Code.
Server
     try
        {
            int port = 6666;
            DatagramSocket ds = new DatagramSocket(port);
           System.out.println("Waiting for Client");
        }
        catch (Exception e)
        {
            System.out.println("Error :" + e);
        }
Client
try
        {
            int port = 5555;
            DatagramSocket ds = new DatagramSocket(port);
        }
        catch (Exception e)
        {
            System.out.println("Error :" + e);
        }


To Send Data In UDP

            byte b[] = new byte[1024];
            b = req.getBytes();
            DatagramPacket dp1 = new DatagramPacket(b,b.length,InetAddress.getLocalHost(),6666);
            ds.send(dp1);

To Receive Data In Data

           byte b[] = new byte[1024];
            DatagramPacket dp1 = new DatagramPacket(b, b.length);
            ds.receive(dp1);
            String str = new String(dp1.getData(),0,dp1.getLength());



RMI(Remote Method Invocation)
Packages
import java.io.*;
import java.net.*;
import java.rmi.*;
import java.rmi.server.*;





Step1 : Interface File(Mathoptr.java)
import java.io.*;
import java.net.*;
import java.rmi.*;
import java.rmi.server.*;
public interface MathOptr extends Remote
{
	public double square(int num) throws Exception;
	public double squareroot(int num) throws Exception;
	public double cube(int num) throws Exception;
	public double cuberoot(int num) throws Exception;
}


Step 2 : Implementation File(MathOptrImpl.java)
import java.io.*;
import java.net.*;
import java.rmi.*;
import java.rmi.server.*;
public class MathOptrImpl extends UnicastRemoteObject implements MathOptr
{
	public MathOptrImpl() throws Exception
	{
		super();
	}

	public double square(int num) throws Exception
	{
		return (num*num);
	}
	public double squareroot(int num) throws Exception
	{
		return(Math.sqrt(num));
	}
	public double cube(int num) throws Exception
	{
		return(num*num*num);
	}
	public double cuberoot(int num) throws Exception
	{
		return(Math.cbrt(num));
	}
}


Step 3 : Server File(MathOptrServer.java)
import java.io.*;
import java.net.*;
import java.rmi.*;
import java.rmi.server.*;
public class MathOptrServer
{
	public static void main(String args[]) throws Exception
	{

		MathOptrImpl obj = new MathOptrImpl();
		Naming.rebind("abc",obj);

		System.out.println("Waiting For Client");
	}
}

Step 4: Client File(MathOptrClient.java)
import java.io.*;
import java.net.*;
import java.rmi.*;
import java.rmi.server.*;
public class MathOptrClient
{
	public static void main(String args[]) throws Exception
	{
		MathOptr obj = (MathOptr) Naming.lookup("abc")	;


		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
                System.out.println("Enter The Number :");
                String req = br.readLine();
		int num = Integer.parseInt(req);


		System.out.println("Square :" + obj.square(num));
		System.out.println("Square Root :" + obj.squareroot(num));
		System.out.println("Cube :" + obj.cube(num));
		System.out.println("Cube Root :" + obj.cuberoot(num));

	}
}





Step 5: Compile all the files(javac *.java);
Step6 : Start rmi registry(Start rmiregistry)

Step7 : Generate Stub File(Rmic MathOptrImpl)

Step8 : Run Server file(java MathOptrServer)
Step 9: Run Client(java MathOptrClient)










NFS Configuration

We need 2 linux machine > Power ON the machines

SERVER
Right click > open terminal>

Step 1: Set IP addr(vim /etc/sysconfig/network-scripts/ifcfg-eth0
then press Enter
After entering press > i
DEVICE=eth0
ONBOOT=yes
BOOTPROTO=static
IPADDR=192.168.1.10
NETMASK=255.255.255.0
(esc+shift+: wq)

# service network restart
# ifconfig(to check ipaddress changed)

Step2: #service iptables stop
# service iptables status
 Step 3: Install the req packages
# cd /media/RHEl(press TAB)
# rpm -ivh  --force --nodeps nfs*
Step 4: mkdir  /nfsserver
# cd /nfsserver/
(nfsserver) # touch f1 f2 f3 f4
# ls
# chmod -R 777 /nfsserver/
# ls (f1 f2 changs to green color)
Step 4:# vim /etc/exports
 /nfsserver  *(rw,sync)
Esc+shift+: )wq
# exportfs -a  (actual export)
# exportfs -v(to view the exported file system)
Step 5: # service nfs restart(if  failed run again command)

Client
Step1: Set IP addr(vim /etc/sysconfig/network-scripts/ifcfg-eth1 then press Enter
After entering press > i
DEVICE=eth1
ONBOOT=yes
BOOTPROTO=static
IPADDR=192.168.1.11
NETMASK=255.255.255.0
(esc+shift+: wq)
# service network restart
# ifconfig(to check ipaddress changed)
Step2: #service iptables stop
# service iptables status
Step 3: Install the req packages
# cd /media/RHEl(press TAB)/P(TAB)
# rpm -ivh  --force --nodeps nfs*
Step 3:  mkdir /client
# ls /client/(will be empty)
# mount 192.168.1.10:/nfsserver /client
# ls  /client/(to check)
To write contenrt
# cat >>  f1
Hgfdiagfjkfghiusjkvsid



Fact
Int f=1;
{f=f*I;}return f;

Rev
Int rev=0;
While(num num me kola 0){Int r=num%10;
Rev = rev*10+r;num=num/10;}return rev;



Even odd
{
If(num%2==0)
{return"the number is even";
}
else{ return "odd";
}


Prime

{
Boolean flag=false;
for(Int I=2;iless num/2;++I)
{
If(num%==0)
{ flag=true}}if(!flag){return"prime"}
Else{return "not prime";}}



Vowels
{
If(name.equals('a') || name.equals('e') || name.equals('i') || name.equals('o') || name.equals('u') )
{Return "vowels";}
Else
{Return"constants";
}
}