middleware lab programs

Ex.No: 1

FILE DOWNLOADING USING RMI

AIM:

To write a java program to download a file using rmi.

HARDWARE SPECIFICATIONS:

1.Mother Board : MSI2. Processor : AMD Athlon (64 bit)3. Hard Disk : 80 GB4. Ram : 640 MB5. Monitor :15’inch HCL6. Keyboard : HCL7. Mouse : HCL Optical Mouse

SOFTWARE SPECIFICATIONS:

1. Microsoft Visual Studio 20082. Net Beans 7.0

ALGORITHM:

Step 1: Start the program.

Step 2: Write the interface code.

Step 3: Write the implementation source for implementing the connection.

Step 4: Write the client and server code to download the file from server.

Step 5: Compile all the java files.

Step 6: Start the rmi registry by c:\jdk1.5\bin>start rmiregistry.

Step 7: Run the server and client in separate window.

Step 8: Stop the program.

1

PROGRAM:

Intr.java:

import java.rmi.RemoteException;

import java.rmi.Remote;

public interface intr extends Remote

{

public byte[ ] loadfile(String filename) throws RemoteException;

}

Impl.java:

import java.io.*;

import java.rmi.*;

import java.rmi.server.UnicastRemoteObject;

public class impl extends UnicastRemoteObject implements intr

{

public impl (String str)throws RemoteException

{

super();

}

public byte[ ] loadfile(String filename)

{

try

{

File f1=new File(filename);

byte buff[ ]=new byte[(int)f1.length() ];

BufferedInputStream bif=new BufferedInputStream(new

FileInputStream(filename));

bif.read(buff,0,buff.length);

bif.close();

return(buff);

}

catch(Exception e)

2

{

}

return(null);

}

}

Serv.java:

import java.io.*;

import java.rmi.*;

public class serv

{

public static void main(String args[ ])

{

try

{

impl f =new impl("serv");

Naming.rebind("serv",f);

System.out.println("\n\t Service Hosted on sever & Client Connected

Now….");

}

catch(Exception e)

{ }

}

}

Clien.java:

import java.io.*;

import java.rmi.*;

public class clien

{

public static void main(String args[ ])

{

try

{

3

String str="rmi://localhost/serv";

intr f =(intr)Naming.lookup(str);

byte[ ]data=f.loadfile(args[0]);

File fs=new File(args [1]);

BufferedOutputStream bf=new BufferedOutputStream(new

FileOutputStream(fs.getName()));

bf.write(data,0,data.length);

bf.flush();

bf.close();

System.out.println("File has been downloaded");

}

catch(Exception e)

{ }

}

}

4

OUTPUT:

C:\jdk1.5\bin>javac *.java

C:\jdk1.5\bin>start rmiregistry

Server window:

C:\jdk1.5\bin>java serv

You Are Connected

Client window:

C:\jdk1.5\bin>java clien t1.txt t2.txt

File has been downloaded

T2.txt window:

RESULT:

Thus the program has been executed and the download has been done successfully.

5

Ex.No: 2

GRAPHICAL SHAPES USING BDK

AIM:

To write a java bean program to draw various graphical shapes using BDK.





ALGORITHM:


Step 2: Create the java bean file Circle.java.

Step 3: Create the mft file Circle.mft.

Step 4: Create a folder in the path C:\j2sdk1.4.2_08\bin\bdk and save all the files.

Step 5: Compile the files using javac *.java.

Step 6: Create the jar file by C:\j2sdk1.4.2_08\bin\bdk>jar cfm Circle.jar

Circle.mft Circle.class.

Step 7: Now open the beanbox from C:\BDK1_1\beans\beanbox and double click

the run command.

Step 8: From the BeanBox opened select LoadJar from file menu.

Step 9: In the dialog box select the jar file that u have created and saved.

Step 10: The jar file will be loaded to the ToolBox named Circle.

Step 11: Now click and drag the ircle to the BeanBox.


6

PROGRAM:

Circle.mft

Name: Circle.class

Java-Bean: True

Circle.java

import java.awt.*;

import java.beans.*;

public class Circle extends Canvas

{

private Color color,bcolor;

public Circle()

{

color=Color.red;

bcolor=Color.blue;

setSize(200,200);

}

public Color getColor()

{

return color;

}

public void setColor(Color c)

{

color=c;

}

public Color getBackgroundColor()

{

return bcolor;

}

public void setBackgroundColor(Color c)

{

bcolor=c;

7

}

public void paint(Graphics g)

{

g.setColor(color);

setBackground(bcolor);

g.fillOval(10,10,30,30);g.fillRect(10,60,40,80);

g.drawLine(60,20,180,20);

g.fillRoundRect(80,150,100,180,20,30);

g.fillArc(120,200,150,200,0,45);

}

}

8

OUTPUT:

C:\j2sdk1.4.2_08\bin\bdk>javac *.java

C:\j2sdk1.4.2_08\bin\bdk>jar cfm Circle.jar Circle.mft Circle.class

C:\j2sdk1.4.2_08\bin\bdk>

BEANBOX:- GRAPHICAL SHAPES

RESULT:

Thus the program has been executed and the drawings were created successfully.

9

Ex.No: 3

BANKING OPERATION USING EJB

AIM:

To write an EJB program to perform the Banking Operations.





ALGORITHM:


Step 2: Put all the required .java files in a folder bank.

Step 3: Set the classpath C:\bank>set

CLASSPATH=C:\Sun\AppServer\lib\j2ee.jar.

Step 4: Compile all the .java files C:\bank>javac *.java.

Step 5: Open the J2EE server Deployement Tool.

Step 6: Select new Application from file menu and give the application display

name and click ok.

Step 7: Select newEnterprise bean from the file menu and add the ejb class file

from edit contents.

Step 8: Select newApplication client from the file menu and add the client class

files from the edit contents.

Step 9: Select deploy from the tools menu.

10

Step 10: Open the dos window and enter into bank folder as C:/Bank.

Step 11: Set application path as C:/Bank>set

APPCPATH=c:\bank\bankAPPClient.jar.

Step 12: Set path as C:/Bank>set path=c:\Sun\AppServer\bin;

Step 13: Run the client using C:/Bank>appclient -client bankAPP.ear -name

bankClient –textauth


11

PROGRAM:

BankHome.java

import javax.ejb.EJBHome;

public interface BankHome extends EJBHome

{

public Bank create(int bal) throws java.rmi.RemoteException,

javax.ejb.CreateException;

}

Bank.java

import javax.ejb.EJBObject;

public interface Bank extends EJBObject

{

public int deposit(int amt)throws java.rmi.RemoteException;

public int withdraw(int amt)throws java.rmi.RemoteException;

}

BankBean.java

import java.util.*;

import java.io.*;

import javax.ejb.SessionBean;

import javax.ejb.SessionContext;

public class BankBean implements SessionBean

{

int balance;

private javax.ejb.SessionContext m_ctx=null;

public void setSessionContext(SessionContext ctx)

{

m_ctx=ctx;

}

public void ejbCreate(int bal) throws

java.rmi.RemoteException,javax.ejb.CreateException

{

balance=bal;

12

}

public void ejbRemove()

{}

public void ejbActivate()

{}

public void ejbPassivate()

{}

public int deposit(int amt)

{

balance+=amt;

return(balance);

}

public int withdraw(int amt)

{

balance-=amt;

return(balance);

}

}

BankClient.java

import javax.naming.Context;

import javax.naming.InitialContext;

import javax.rmi.PortableRemoteObject;

import java.io.*;

public class bankClient

{

public static void main(String[] args)

{

Bank myBankRemote=null;

BankHome myBankHome=null;

int amount,balance;

try

{

//The javax.naming.InitialContext class implements the //Context interface

and serves as our entry point to a naming system

13

InitialContext initial = new InitialContext();

String JNDIName="ejb/SimpleBank";

Object obj=initial.lookup(JNDIName);

myBankHome=(BankHome)PortableRemoteObject.narrow(obj,BankHom

e.class);

myBankRemote=myBankHome.create(5000);

DataInputStream in=new DataInputStream(System.in);

while(true)

{

System.out.println("Banking Operations\n1.Deposit\n2.Withdraw\

n3.Exit");

System.out.println("Enter ur choice");

int ch=Integer.parseInt(in.readLine());

switch(ch)

{

case 1://deposit

System.out.println("Enter the deposit amount");

amount=Integer.parseInt(in.readLine());

balance=myBankRemote.deposit(amount);

System.out.println("Total amount is"+balance);

break;

case 2://withdraw

System.out.println("Enter the withdraw amount");

amount=Integer.parseInt(in.readLine());

balance=myBankRemote.withdraw(amount);

System.out.println("Balance is"+balance);

break;

case 3:

System.exit(0);

}}} catch (Exception ex) {

System.err.println("Caught an unexpected exception!");

ex.printStackTrace();

}

} }

14

OUTPUT:

C:\>cd bank

C:\bank>set CLASSPATH=C:\Sun\AppServer\lib\j2ee.jar

C:\bank>javac *.java

C:\bank>set APPCPATH=c:\bank\bankAPPClient.jar

C:\bank>set path=c:\Sun\AppServer\bin;

C:\bank>appclient -client bankAPP.ear -name bankClient -textauth

Banking Operations

1. Deposit

2. Withdraw

3. Exit

Enter ur choice: 1

Enter the deposit amount

1000

Total amount is6000

Banking Operations

1. Deposit

2. Withdraw

3. Exit

Enter ur choice: 2

Enter the withdraw amount

1000

Balance is5000

Banking Operations

1. Deposit

2. Withdraw

3. Exit

Enter ur choice: 3

RESULT:

Thus the program has been executed and all the banking operations were done

successfully.

15

Ex.No: 4

LIBRARY OPERATION USING EJB

AIM:

To write an EJB program to perform the library operations.





ALGORITHM:


Step 2: Put all the required .java files in a folder bank.

Step 3: Set the classpath C:\Library>set

CLASSPATH=C:\Sun\AppServer\lib\j2ee.jar.

Step 4: Compile all the .java files C:\Library>javac *.java.

Step 5: Open the J2EE server Deployement Tool.

Step 6: Select new Application from file menu and give the application display

name and click ok.

Step 7: Select newEnterprise bean from the file menu and add the ejb class file

from edit contents.

Step 8: Select newApplication client from the file menu and add the client class

files from the edit contents.

Step 9: Select deploy from the tools menu.

Step 10: Open the dos window and enter into library folder as C:/Library.

Step 11: Set application path as C:/Library>set

16

APPCPATH=c:\Library\LibraryAPPClient.jar.

Step 12: Set path as C:/Library>set path=c:\Sun\AppServer\bin;

Step 13: Run the client using C:/Library>appclient -client LibraryAPP.ear -name

LibraryClient –textauth


17

PROGRAM:

LibraryHome.java

import javax.ejb.*;

import java.rmi.*;

public interface LibraryHome extends EJBHome

{

public Library create(String uname,String uid) throws

RemoteException,CreateException;

}

Library.java

import javax.ejb.*;

import java.rmi.*;

public interface Library extends EJBObject

{

public String issue(String bn,int nobook)throws RemoteException;

public String ret(String bn,int days)throws RemoteException;

}

LibraryBean.java

import javax.ejb.*;

import javax.naming.*;

import java.rmi.*;

public class LibraryBean implements SessionBean

{

String username;

String userid;

String bookname;

int nobook;

18

public void ejbCreate(String uname,String uid)

{

username=uname;

userid=uid;

}

public void ejbRemove()

{}

public void ejbActivate()

{}

public void ejbPassivate()

{}

public void setSessionContext(SessionContext ctx)

{}

public String issue(String bname,int nbook)

{

bookname=bname;

nobook=nbook;

if(nobook<=30)

return"Available AND &issued";

else

return "Not Available";

}

public String ret(String bname,int days)

{

bookname=bname;

if(days<30)

return"Returned without fine";

else

return" Returned with fine";

}

}

19

LibraryClient.java

import javax.ejb.*;

import javax.naming.*;

import java.io.*;

import javax.rmi.*;

import java.util.*;

import javax.naming.Context;

import javax.naming.InitialContext;

import javax.rmi.PortableRemoteObject;

public class LibraryClient

{

public static void main(String args[])throws Exception

{

Library myLibrary=null;

LibraryHome myLibraryHome=null;

try

{

InitialContext initial = new InitialContext();

String JNDIName="ejb/SimpleLibrary";

Object obj=initial.lookup(JNDIName);

myLibraryHome=(LibraryHome)PortableRemoteObject.narrow(obj,Librar

yHome.class);

int z,c1; String s,e,name,no,e1;

int nobook;

DataInputStream m=new DataInputStream(System.in);

System.out.println("Library Operation");

System.out.println("Enter username");

name=m.readLine();

System.out.println("Enter user ID");

no=m.readLine();

myLibrary=myLibraryHome.create(name,no);

while(true)

{ System.out.println("1.Issue");

20

System.out.println("\n2.Return");

System.out.println("\n3.Exit");

System.out.println("Enter ur choice");

z=Integer.parseInt(m.readLine());

switch(z)

{ case 1:

System.out.println("Enter Book name");

s=m.readLine();

System.out.println("Enter no of books required");

nobook=Integer.parseInt(m.readLine());

e=myLibrary.issue(s,nobook);

System.out.println(e);

break;

case 2:

System.out.println("Enter Book name");

s=m.readLine();

System.out.println("Enter days");

c1=Integer.parseInt(m.readLine());

e1=myLibrary.ret(s,c1);

System.out.println(e1);

break;

case 3:

myLibrary.remove();

System.exit(0);

break;

}

}

}

catch(Exception e)

{}

}

}

21

OUTPUT:

C:\library>set CLASSPATH=C:\Sun\AppServer\lib\j2ee.jar

C:\library>javac *.java

C:\library>set APPCPATH=C:\library\LibraryAppClient.jar

C:\library>set path=C:\Sun\AppServer\bin;

C:\library>appclient -client LibraryApp.ear -name LibraryClient -textauth

Library Operation

Enter username

mani

Enter user ID

123

Menu

1. Issue

2. Return

3. Exit

Enter ur choice

1

Enter Book name

JAVA

Enter no of books required

15

Available AND &issued

Menu

1. Issue

2. Return

3. Exit

Enter ur choice

2

Enter Book name

JAVA

Enter days

25

Returned without fine

22

Menu

1. Issue

2. Return

3. Exit

Enter ur choice

3

C:\library>

RESULT:

Thus the program has been executed and all the library operations were done

successfully.

23

Ex.No: 5

FILE OPERATIONS

AIM:

To write a visual basic program to perform the various file operations.





ALGORITHM:


Step 2: Declare the necessary packages.

Step 3: Design the form with one Rich textbox and following buttons

Create

Read

Save

Copy

Delete

Step 4: Click the create button to crete a new file.

Step 5: Click the read button to get the file and display the contents.

Step 6: Click the save button the save the contents into the file.

Step 7: Click the copy button to copy the contents to another file.

Step 8: Click the delete button to delete the existing file.


24

PROGRAM:

Imports System.IO

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)

Handles Button1.Click

Dim opndlg As New OpenFileDialog

Dim Filearea As StreamReader

opndlg.Filter = "All Files(*.*)|*.*|TextFiles(*.txt)|*.txt"

opndlg.ShowDialog()

Filearea = New StreamReader(opndlg.FileName)

RichTextBox1.Text = Filearea.ReadToEnd

Filearea.Close()

End Sub



Dim savdlg As New SaveFileDialog

Dim Filewri As StreamWriter

savdlg.Filter = "All Files(*.*)|*.*|TextFiles(*.txt)|*.txt"

savdlg.ShowDialog()

Filewri = New StreamWriter(savdlg.FileName)

Filewri.WriteLine(RichTextBox1.Text)

Filewri.Close()

End Sub



Dim fs As FileStream

Dim Filename As String = "c:\sample.txt"

If File.Exists(Filename) Then

MsgBox("File Exists")

Else

fs = New FileStream(Filename, FileMode.Create, FileAccess.ReadWrite)

Dim byt() As Byte = System.Text.UTF8Encoding.UTF8.GetBytes("Richtextbox1.text")

fs.Write(byt, 0, byt.Length)

25

fs.close()

End If

End Sub



Dim fname As String

fname = InputBox("Enter full path of delete filename")

If File.Exists(fname) Then

File.Delete(fname)

MsgBox("SUCESSFULLY DELETED")

Else

MsgBox("File was not available")

End If

End Sub



Dim file1 As String = InputBox("Enter full path of sourcefle name")

Dim file2 As String = InputBox("Enter full path of destination(new file name)")

If Not File.Exists(file1) Then

MsgBox("File was not available")

Else

File.Copy(file1, file2)

MsgBox("sucessfully copied")

End If

End Sub

End Class

26

OUTPUT:

FORM 1:- CREATING A FILE

27

FORM 2:- SAVING THE FILE

28

FORM 3:- READING A FILE

29

FORM 4.1:- COPYING A FILE

30

FORM 4.2:- COPYING DESTINATION

31

FORM 5:- DELETING A FILE

RESULT:

Thus the program has been executed and all the file read and write operations were done

successfully.

32

Ex:No: 6

CURRENCY CONVERSION

AIM:

To write a program in VB.NET for currency conversion operation.





ALGORITHM:

Step1: Start the program.

Step2: Create a class.

Step3: Design a window with needed textboxes, combo box and buttons.

Step4: Write a coding for combo box to insert all the options based on currency

types.

Step5: Write a coding for textbox1 as to show the value of currency which is

selected in combo box.

Step6: Read the input in textbox2.

Step7: Write a coding for button1 as to calculate the amount.

Step8: Display the amount in textbox3.

Step9: Stop the program.

33

PROGRAM:

Public Class Form1

Dim ex, amt As Single

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As

System.EventArgs) Handles Button1.Click

amt = ex * Val(TextBox2.Text)

TextBox3.Text = amt

End Sub

Private Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles

Button2.Click

End

End Sub

Private Sub ComboBox1_Click(ByVal sender As Object, ByVal e As System.EventArgs)

Handles ComboBox1.Click

ComboBox1.Items.Add("US DOLLAR")

ComboBox1.Items.Add("STERLING")

ComboBox1.Items.Add("DINAR")

ComboBox1.Items.Add("FRANC")

ComboBox1.Items.Add("EURO")

End Sub

Private Sub TextBox1_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs)

Handles TextBox1.GotFocus

Select Case ComboBox1.Text

Case "US DOLLAR"

ex = 42.5

Case "STERLING"

ex = 71.3

Case "DINAR"

ex = 25.32

Case "FRANC"

34

ex = 31.58

Case "EURO"

ex = 41.58

End Select

TextBox1.Text = ex

End Sub

End Class

35

OUTPUT:

FORM 1:- CURRENCY CONVERTION

RESULT:

Thus the currency conversion program has been executed and completed successfully.

36

Ex.No: 7

ENCRYPTION AND DECRYPTION

AIM:

To write a visual basic program to perform the Encryption and Decryption operations.





ALGORITHM:


Step 2: Declare the necessary packages.

Step 3: Design the form with Rich textbox and three buttons.

Step 4: In the encryption coding create a text file with access permission to write.

Step 5: Use CreateEncryptor to convert the text to Unicode Encoding.

Step 6: In the decryption coding open the file with the access permission to read.

Step 7: Use CreateDecryptor to convert the encoding into original text.

Step 8: Encrypted text can be read in the Rich textbox.


37

PROGRAM:

Imports System.IO

Imports System.Security.Cryptography

Imports System.Text

Public Class Form1

Inherits System.Windows.Forms.Form

Dim des As New DESCryptoServiceProvider



Dim fs As New FileStream("C:\book.txt", FileMode.Create, FileAccess.Write)

Dim bytearrayinput As Byte() = New UnicodeEncoding().GetBytes(RichTextBox1.Text)

Dim desencrypt As ICryptoTransform = des.CreateEncryptor()

Dim cryptostream As New CryptoStream(fs, desencrypt, CryptoStreamMode.Write)

cryptostream.Write(bytearrayinput, 0, bytearrayinput.Length)

cryptostream.Close()

RichTextBox1.Text = " "

MsgBox("Data is Encrypted")

End Sub



Dim fsread As New FileStream("c:\book.txt", FileMode.Open, FileAccess.Read)

Dim desdecrypt As ICryptoTransform = des.CreateDecryptor()

Dim cryptostreamdecr As New CryptoStream(fsread, desdecrypt,

CryptoStreamMode.Read)

RichTextBox1.Text = New StreamReader(cryptostreamdecr, New

UnicodeEncoding).ReadToEnd()

MsgBox("Data is Decrypted")

End Sub



Dim filearea As StreamReader

filearea = New StreamReader("c:\book.txt")

38

RichTextBox1.Text = filearea.ReadToEnd

filearea.Close()

End Sub

End Class

39

OUTPUT:

FORM 1:- ENCRYPTION

40

FORM 2:- DECRYPTION

RESULT:

Thus the encryption and decryption operation has been performed successfully.

41

Ex.No: 8

STUDENT DATABASE

AIM:

To write a Visual basic .Net Program to maintain Student databases.





ALGORITHM:


Step 2: Create the Student database in MS Access with the needed fields.

Step 3: Design the form with necessary Textboxes and buttons.

Step 4: Connect the database by using the Provider

"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=F:\spstu.mdb"

Step 5: Enter the data and click the insert button then the data will be inserted

into the database.

Step 6: Specify the roll no in the input box corresponding data will be displayed.

Step 7: Data will be updated into the database by clicking the update button.

Step 8: Specify the roll no in the input box corresponding data will be deleted.


42

PROGRAM:

Public Class Form1

Dim con As New OleDb.OleDbConnection ("Provider=Microsoft.Jet.OLEDB.4.0;Data

Source=F:\spstu.mdb")

Dim selstu1



Dim rn, ag, na, cl

Dim strcmd As String

rn = TextBox1.Text

na = TextBox2.Text

ag = TextBox3.Text

cl = TextBox4.Text

con.Open()

strcmd = "insert into spstu(rollno,name,age,class)values(" & rn & " ,' " & na & " ',"

& ag & ",'" & cl & " ' ) "

Dim selstu As Data.OleDb.OleDbCommand = New

Data.OleDb.OleDbCommand(strcmd, con)

selstu.ExecuteNonQuery()

MsgBox("Record inserted")

con.Close()

TextBox1.Text = " "

TextBox2.Text = " "

TextBox3.Text = " "

TextBox4.Text = " "

End Sub



con.Open()

Dim s As String

Dim no = InputBox("Enter the roll number to search")

s = "select * from spstu where rollno=" & no & " "

43

Dim selstu1 As Data.OleDb.OleDbCommand = New

Data.OleDb.OleDbCommand(s, con)

Dim dr As Data.OleDb.OleDbDataReader

dr = selstu1.ExecuteReader

Do While dr.Read

TextBox1.Text = dr.Item("rollno")

TextBox2.Text = dr.Item("name")

TextBox3.Text = dr.Item("age")

TextBox4.Text = dr.Item("class")

Loop

con.Close()

End Sub



Dim no = TextBox1.Text

con.Open()

Dim na = TextBox2.Text

Dim s As String

s = " update spstu set name = ' " & na & " 'where rollno=" & no & " "


Data.OleDb.OleDbCommand(s, con)

selstu2.ExecuteReader()

MsgBox("Record updated")

con.Close()

End Sub



con.Open()

Dim temp

Dim no = InputBox("Enter the number to be deleted")


44

Data.OleDb.OleDbCommand("delete from spstu where rollno=" & no & " ", con)

'Dim dr As Data.OleDb.OleDbDataReader

temp = selstu1.ExecuteReader()

MsgBox("Record deleted")

con.Close()

End Sub

End Class

45

OUTPUT:

FORM 1:- INSERTION

46

FORM 2.1:- DISPLAY

47

FORM 2.2:- DISPLAYED DETAILS

48

FORM 3:- UPDATION

49

FORM 4:- DELETION

RESULT:

Thus the student database program has been executed and completed successfully.

50

Ex.No: 9

STOCK MARKET EXCHANGE USING CORBA

AIM:

To write a java program to retrieve stock market exchange information using corba.





ALGORITHM:


Step 2: Create the simplestocks.idl file.

Step 3: Write the implementation, server, and client coding.

Step 4: Create a new folder in C directory and save all the above files in that

folder.

Step 5: Compile the idl file using (idlj –fall –oldImplBase simplestocks.idl) in dos

window.

Step 6: Now compile all the java files by (javac *.java).

Step 7: Start the tnameserv and minimize the window.

Step 8: Run the server and client in separate windows.

Step 9: Save the program.


51

PROGRAM:

Simplestocks.idl

module simplestocks

{

interface stockmarket

{

float get_price(in string symbol);

};

};

Stockmarketimpl.java

import org.omg.CORBA.*;

import simplestocks.*;

public class stockmarketimpl extends _stockmarketImplBase

{

public float get_price(String symbol)

{

float price=0;

for(int i=0;i<symbol.length();i++)

{

price+=(int)symbol.charAt(i);

}

price/=5;

return price;

}

public stockmarketimpl()

{

super();

}

}

Stockmarketserver.java


import org.omg.CosNaming.*;

52


public class stockmarketserver

{

public static void main(String args[])

{

try

{

ORB orb=ORB.init(args,null);

Stockmarketimpl d=new stockmarketimpl();

orb.connect(d);

org.omg.CORBA.Object

objRef=orb.resolve_initial_references("NameService");

NamingContext ncRef=NamingContextHelper.narrow(objRef);

NameComponent nc=new NameComponent("NASDAQ","");

NameComponent path[]={nc};

ncRef.rebind(path,(d));

System.out.println("stock market server is up and ready");

Thread.currentThread().join();

}

catch(Exception e)

{}

}

}

Stockmarketclient.java




public class stockmarketclient

{


{

try

{

53







stockmarket market=stockmarketHelper.narrow(ncRef.resolve(path));

System.out.println("price of my company is"+market.get_price("b"));

}

catch(Exception e)

{}

}

}

54

OUTPUT:

C:\corba>idlj -fall -oldImplBase simplestocks.idl

C:\corba>javac *.java

C:\corba>tnameserv

Initial Naming Context:

IOR:000000000000002849444c3a6f6d672e6f72672f436f734e616d696e672f4e616d696e67436f

6e746578743a312e3000000000010000000000000058000101000000000e3139322e3136382e30

2e31353000042100000019afabcaff0000000238da7c4e000000080000000000000000010000000

000000100000001000000140000000000010020000000000001010000000000

TransientNameServer: setting port for initial object references to: 900

Ready.

Server Window:

C:\corba>java stockmarketserver

stock market server is up and ready

Client Window:

C:\corba>java stockmarketclient

price of my company is19.6

RESULT:

Thus the stock market program has been executed and completed successfully

55

Ex.No: 10

WEATHER FORECASTING USING CORBA

AIM:

To write java program to display the weather forecasting using corba.





ALGORITHM:


Step 2: Create the simpletemps.idl file.

Step 3: Write the implementation, server, and client coding.

Step 4: Create a new folder in C directory and save all the above files in that

folder.

Step 5: Compile the idl file using (idlj –fall –oldImplBase simpletemps.idl) in dos

window.

Step 6: Now compile all the java files by (javac *.java).

Step 7: Start the tnameserv and minimize the window.

Step 8: Run the server and client in separate windows.

Step 9: Save the program.


56

PROGRAM:

Simpletemps.idl

module simpletemps

{

interface weatherforecast

{

string get_tmp(in float a);

};

};

Weatherforecastimpl.java


import simpletemps.*;

public class weatherforecastimpl extends _weatherforecastImplBase

{

public String get_tmp(float a)

{

String c;

if(a<0)

c="****Too cool****";

else if(a<=10)

c="**** cool****";

else if(a<=20)

c="**** Moderate****";

else if(a<=30)

c="**** Hot****";

else

c="****Too Hot****";

return c;

}

public weatherforecastimpl()

{

super();

57

}

}

Weatherforecastserver.java




public class weatherforecastserver

{


{

try

{


weatherforecastimpl d=new weatherforecastimpl();

orb.connect(d);






ncRef.rebind(path,(d));

System.out.println("weather forecast server is up and ready");

Thread.currentThread().join();

}

catch(Exception e)

{}

}

}

Weatherforecastclient.java




import java.io.*;

public class weatherforecastclient

58

{


{

try

{

System.out.println("Enter the temperature");

java.io.DataInputStream in=new java.io.DataInputStream(System.in);

float e=Float.parseFloat(in.readLine());







weatherforecast wthr=weatherforecastHelper.narrow(ncRef.resolve(path));

System.out.println("The climate is now : "+wthr.get_tmp(e));

}

catch(Exception e)

{}

}

}

59

OUTPUT:

tnameserv

C:\>cd corba

C:\corba>idlj -fall -oldImplBase simpletemps.idl

C:\corba>javac *.java

C:\corba>tnameserv

Initial Naming Context:

IOR:000000000000002849444c3a6f6d672e6f72672f436f734e616d696e672f4e616d696e67436f

6e746578743a312e3000000000010000000000000058000101000000000e3139322e3136382e30

2e

31353000043400000019afabcaff000000023a6c237700000008000000000000000001000000000

0

000100000001000000140000000000010020000000000001010000000000

TransientNameServer: setting port for initial object references to: 900

Ready.

Weatherforecast.Server

C:\>cd corba

C:\corba>java weatherforecastserver

C:\corba>java weatherforecastserver

weather forecast server is up and ready

Weatherforecast.Client

C:\corba>java weatherforecastclient

Enter the temperature

10

climate is**** cool****



50

climate is****Too Hot****

60



30

climate is**** Hot****

RESULT:

Thus the Weather Forecast program has been executed and completed successfully.

61

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