MADHA ENGINEERING COLLEGE

DEPARTMENT OF CSE

REGULATION-2008

CS2306 – JAVA LAB

LAB MANUAL

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SYLLABUS

1. Develop Rational number class in Java. Use Java Doc comments for documentation. Your implementation should use efficient representation for a rational number, i.e. (500 / 1000) should be represented as (½).

2. Develop Date class in Java similar to the one available in java.util package. Use Java Doc comments.

3. Implement Lisp-like list in Java. Write basic operations such as 'car', 'cdr', and 'cons'. If L is a list [3, 0, 2, 5], L.car () returns 3, while L.cdr() returns [0,2,5].

4. Design a Java interface for ADT Stack. Develop two different classes that implement this interface, one using array and the other using linked-list. Provide necessary exception handling in both the implementations.

5. Design a Vehicle class hierarchy in Java. Write a test program to demonstrate polymorphism.

6. Design classes for Currency, Rupee, and Dollar. Write a program that randomly generates Rupee and Dollar objects and write them into a file using object serialization. Write another program to read that file, convert to Rupee if it reads a Dollar, and while leave the value as it is if it reads a Rupee.

7. Design a scientific calculator using event-driven programming paradigm of Java.

8. Write a multi-threaded Java program to print all numbers below 100,000 that are both prime and Fibonacci number (some examples are 2, 3, 5, 13, etc.). Design a thread that generates prime numbers below 100,000 and writes them into a pipe. Design another thread that generates Fibonacci numbers and writes them to another pipe. The main thread should read both the pipes to identify numbers common to both.

9. Develop a simple OPAC system for library using even-driven and concurrent programming paradigms of Java. Use JDBC to connect to a back-end database.

10.Develop multi-threaded echo server and a corresponding GUI client in Java.

11. [Mini-Project] Develop a programmer's editor in Java that supports syntax-highlighting, compilation support, debugging support, etc.

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1. IMPLEMENTATION OF RATIONAL NUMBER

Develop Rational number class in Java. Use JavaDoc comments for documentation. Your implementation should use efficient representation for a rational number, i.e. (500 / 1000) should be represented as (½).

ALGORITHM:STEP 1: Get two inputs from the user through command line arguments.STEP 2: Store the numerator to variable a and denominator to variable b.STEP 3: If both a and b are either positive or negative, set the flag as 0.STEP 4: If either a or b is negative, set flag as 1.STEP 5: Compare the values of a and b and assign the lowest value to c.STEP 6: Set the for loop for i=2.STEP 7: If both a and b values are divisible by i, then perform

(i) a=a/i;(ii) b=b/i;(ii) i=1;

STEP 8: Repeat the loop if the value of i is less than c. Break the loop if the condition fails.STEP 9: If flag is 1, display the result as negative number; else display it as positive number.

RationalClass.java

import java.util.*;

/***@author Sreekandan.K*/

public class RationalClass{

 /** The Numerator part of Rational */

 private int numerator; 

 /** The Denominator part of Rational */

 private int denominator;     /**

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 create and initialize a new Rational object */

 public RationalClass(int numerator,int denominator) {  if(denominator==0)  {   throw new RuntimeException("Denominator is zero");  }  int g=gcd(numerator,denominator);  if(g==1)  {   System.out.println("No Common Divisor for Numerator and Denominator");   this.numerator=numerator;   this.denominator=denominator;  }  else  {   this.numerator=numerator/g;   this.denominator=denominator/g;  } }

 /** return string representation */

 public String display() {  return numerator+"/"+denominator; }

 /** @param m @param n @return Greatest common divisor for m and n */

 private static int gcd(int n,int d) {  if(d==0)  return n;  else  return gcd(d,n%d); }

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2. IMPLEMENTATION OF DATE SERVER

Develop Date class in Java similar to the one available in java.util package. Use Java Doc comments.

ALGORITHM:STEP 1: Create a package which consists of constructors with the following arguments: i) Default

ii)Taking 3 arguments year, day and month iii)Taking 5 arguments year, day, month, hours and minutes iv)Taking 6 arguments year, day, month, hour, minutes and secondsSTEP 2: Get the year, month, date, hours, minutes, seconds using the getYear(), getMonth(), getDate(), getHours(), getMinutes(), getSeconds() methods.STEP 3: Set all these details using set methods.STEP 4: After()-the after() method returns true if the current date comes after the specified date else it returns falseSTEP 5: Before()-the before()method returns true if the current date comes before the specified date else it returns falseSTEP 6: Compare()-the compare() method compares the current date with the specified date and returns 0 if it is equal,if after it returns 1 and if before it returns -1.

DateFormatDemo.java

import java.text.*;import java.util.*;/** *Class DateFormatDemo formats the date and time by using java.text package**/public class DateFormatDemo{ public static void main(String args[]) { /**  * @see java.util package */  Date date=new Date(); /**  * @see java.text package */  DateFormat df;  System.out.println("Current Date and Time - Available in java.util Package:");  System.out.println("-------------------------------------------------------");  System.out.println(date);  System.out.println();

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  System.out.println("Formatted Date - Using DateFormat Class from java.text Package:");  System.out.println("---------------------------------------------------------------");  df=DateFormat.getDateInstance(DateFormat.DEFAULT);  System.out.println("Default Date Format:"+df.format(date));  df=DateFormat.getDateInstance(DateFormat.SHORT);  System.out.println("Date In Short Format:"+df.format(date));  df=DateFormat.getDateInstance(DateFormat.MEDIUM);  System.out.println("Date In Medium Format:"+df.format(date));  df=DateFormat.getDateInstance(DateFormat.LONG);  System.out.println("Date In Long Format:"+df.format(date));  df=DateFormat.getDateInstance(DateFormat.FULL);  System.out.println("Date In Full Format:"+df.format(date));  System.out.println();  System.out.println("Formatted Time - Using DateFormat Class from java.text Package:");  System.out.println("---------------------------------------------------------------");  df=DateFormat.getTimeInstance(DateFormat.DEFAULT);  System.out.println("Default Time Format:"+df.format(date));  df=DateFormat.getTimeInstance(DateFormat.SHORT);  System.out.println("Time In Short Format:"+df.format(date));  df=DateFormat.getTimeInstance(DateFormat.MEDIUM);  System.out.println("Time In Medium Format:"+df.format(date));  df=DateFormat.getTimeInstance(DateFormat.LONG);  System.out.println("Time In Long Format:"+df.format(date));  df=DateFormat.getTimeInstance(DateFormat.FULL);  System.out.println("Time In Full Format:"+df.format(date));  System.out.println();  System.out.println("Formatted Date and Time - Using SimpleDateFormat Class from java.text Package:");  System.out.println("------------------------------------------------------------------------------"); /**  * @see java.text package */  SimpleDateFormat sdf;  sdf=new SimpleDateFormat("dd MMM yyyy hh:mm:sss:S E w D zzz");  System.out.println(sdf.format(date)); }}

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3. IMPLEMENTATION OF LISP-LIKE LIST

Implement Lisp-like list in Java. Write basic operations such as 'car', 'cdr', and 'cons'. If L is a list [3, 0, 2, 5], L.car() returns 3, while L.cdr() returns [0,2,5].ALGORITHMSTEP 1: Create a node of a list having data part and link part.STEP 2: Create a menu having the following choices : insert, car, cdr, adjoin and display.STEP 3: Read the choice from the user and call the respective m ethods.STEP 4: Create another class which implements the same interface to implement the concept of stack through linked list.INSERTSTEP 1: Create an object of node and append to the list.CARSTEP 1: Return the first node data.CDRSTEP 1: Return all the node (data part) in the list except the first node.ADJOINSTEP 1: Check if the node to be inserted is already present in the list, if not present append to the list.LispOperation.javaimport java.util.*;/****/class Lisp{ public Vector car(Vector v) {  Vector elt=new Vector();  elt.addElement(v.elementAt(0));  return elt; } public Vector cdr(Vector v) {  Vector elt=new Vector();  for(int i=1;i<v.size();i++)  elt.addElement(v.elementAt(i));  return elt; } public Vector cons(int x, Vector v) {  v.insertElementAt(x,0);  return v; }}

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4. IMPLEMENTATION OF STACK

Design a Java interface for ADT Stack. Develop two different classes that implement this interface, one using array and the other using linked-list. Provide necessary exception handling in both the implementations.

ALGORITHMSTEP 1: Create an interface which consists of three methods namely PUSH, POP and DISPLAYSTEP 2: Create a class which implements the above interface to implement the concept of stack through ArraySTEP 3: Define all the methods of the interface to push any element, to pop the top element and to display the elements present in the stack.STEP 4: Create another class which implements the same interface to implement the concept of stack through linked list.STEP 5: Repeat STEP 4 for the above said class also.STEP 6: In the main class, get the choice from the user to choose whether array implementation or linked list implementation of the stack.STEP 7: Call the methods appropriately according to the choices made by the user in the previous step.STEP 8: Repeat step 6 and step 7 until the user stops his/her execution

StackADT.java

import java.io.*;import java.util.*;interface stackInterface{ int n=50; public void pop(); public void push(); public void display();}class stack implements stackInterface{ int arr[]=new int[n]; int top=-1; Scanner in=new Scanner(System.in); public void push() {  try  {   System.out.println("Enter The Element of Stack");   int elt=in.nextInt();   arr[++top]=elt;  }  catch (Exception e)  {

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   System.out.println("e");  } } public void pop() {  int pop=arr[top];  top--;  System.out.println("Popped Element Is:"+pop); } public void display() {  if(top<0)  {   System.out.println("Stack Is Empty");   return;  }  else  {   String str=" ";   for(int i=0;i<=top;i++)   str=str+" "+arr[i];   System.out.println("Stack Elements Are:"+str);  } }}/****/

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5. IMPLEMENTATION OF VEHICLE CLASS USING POLYMORPHISM

Design a Vehicle class hierarchy in Java. Write a test program to demonstrate Polymorphism.

ALGORITHMSTEP 1: Create an abstract class named vehicle with abstract method Display and a concrete method Input.STEP 2: Define the input method by prompting the user to enter the values for name, owner, type, number, engine capacity, seating capacity for the vehicle; all the inputs taken in the form string.STEP 3: Extend three classes namely Air, Water and Land from the base class.STEP 4: Define the method display under the class Air by displaying all the entered values.STEP 5: Repeat step 4 for the class Water.STEP 6: Extend the input method for the class Land by taking in the value of wheeling capacity for the vehicle in the form of string.STEP 7: In the main method create a reference for the abstract class and create a switch case to perform operations on the opted class.STEP 8: Under each class create a switch case to either enter the data or to display the transport report.STEP 9: Repeat the main menu on the user's choice.STEP 10: Create array of objects under each class and call the methods by assigning the values of the created objects to the reference object, to show polymorphism.

VehicleDemo.java

import java.io.*;class Vehicle{ String regno; int model; Vehicle(String r, int m) {  regno=r;  model=m; } void display() {  System.out.println("Registration Number:"+regno);  System.out.println("Model Number:"+model); }}class Twowheeler extends Vehicle{

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 int wheel; Twowheeler(String r,int m,int n) {  super(r,m);  wheel=n; } void display() {  System.out.println("Vehicle : Two Wheeler");  System.out.println("=====================");  super.display();  System.out.println("Number of Wheels:"+wheel+"\n"); }}class Threewheeler extends Vehicle{ int leaf; Threewheeler(String r,int m,int n) {  super(r,m);  leaf=n; } void display() {  System.out.println("Vehicle : Three Wheeler");  System.out.println("=======================");  super.display();  System.out.println("Number of Leaf:"+leaf+"\n"); }}class Fourwheeler extends Vehicle{ int leaf; Fourwheeler(String r,int m,int n) {  super(r,m);  leaf=n; } void display() {  System.out.println("Vehicle : Four Wheeler");  System.out.println("======================");  super.display();  System.out.println("Number of Leaf:"+leaf); }}/****/

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6. IMPLEMENTATION OF CURRENCY CONVERTER

Design classes for Currency, Rupee, and Dollar. Write a program that randomly generates Rupee and Dollar objects and write them into a file using object serialization. Write another program to read that file, convert to Rupee if it reads a Dollar, while leave the value as it is if it reads a Rupee.ALGORITHM FOR PROGRAM 1:STEP 1: Create a class named currency that implements the serializable interface and also it is the base class for rupee and dollar classes.STEP 2: Create an object for ObjectOutputStream to open a file in write mode using FileOutputStream.STEP 3: Read the user choice to enter rupee or dollar amount.STEP 4: Generate random numbers as the value of rupee or dollar.STEP 5: If choice is rupee then, append "Rs" to the value generated, else if choice is dollar append "$" to the value generated.STEP 6: Display the appended String and also write it into the file opened using the writeObject() method.STEP 7: Close the file.

ALGORITHM FOR PROGRAM 2: STEP 1: Create a class named currency that implements the serializable interface and also it is the base class for rupee and dollar classes.STEP 2: Create an object for ObjectInputStream to open the file created in program1 in read mode using FileInputStream.STEP 3: If the file does not exist or if it is empty show exceptions.STEP 4: While the End of file is not reached, do the following... (i) If the value read is a dollar convert into rupee and print to the user otherwise print the rupee as such.STEP 5: End the program.

writeObj.java

import java.io.*;import java.util.*;abstract class Currency implements Serializable{ protected double money; public abstract double getValue(); public abstract String printObj(); public Currency(double money) {  this.money=money; }}class Dollar extends Currency

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{ public Dollar(int money) {  super(money); } public double getValue() {  return this.money*51; } public String printObj() {  String object="Object Name : Dollar\nUSD : $"+this.money+"\nINR : Rs"+getValue()+"\n";  return object; }}class Rupee extends Currency{ public Rupee(int amount) {  super(amount); } public double getValue() {  return this.money; } public String printObj() {  String object="Object Name : Rupee \nINR : Rs "+getValue()+"\n";  return object; }}/****/

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7. IMPLEMENTATION OF CALCULATOR

Develop a scientific calculator using even-driven programming paradigm of Java.

ALGORITHM:STEP 1: Create a panel consisting of Buttons for various scientific operations.STEP 2: Create Button actions.STEP 3: Place the panel onto a frame.STEP 4: Associate each Button click with the corresponding actionlistener.

SimpleCalculator.java

import java.awt.*;import java.awt.event.*;import javax.swing.*;import java.lang.*;/****/public class SimpleCalculator{ public static void main(String[] args) {  CalcFrame cf=new CalcFrame();  cf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  cf.setVisible(true); }}class CalcFrame extends JFrame{ public CalcFrame() {  setTitle("CALCULATOR");  CalcPanel panel=new CalcPanel();  add(panel);  pack(); }}class CalcPanel extends JPanel{ JButton display; JPanel panel; double result; String lastcmd; boolean start; public CalcPanel() {

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  setLayout(new BorderLayout());  result=0;  lastcmd="=";  start=true;  display=new JButton("0");  display.setEnabled(false);  add(display,BorderLayout.NORTH);  ActionListener insert=new InsertAction();  ActionListener cmd=new CommandAction();  panel=new JPanel();  panel.setLayout(new GridLayout(5,4));  addButton("1",insert);  addButton("2",insert);  addButton("3",insert);  addButton("/",cmd);  addButton("4",insert);  addButton("5",insert);  addButton("6",insert);  addButton("*",cmd);  addButton("7",insert);  addButton("8",insert);  addButton("9",insert);  addButton("-",cmd);  addButton("0",insert);  addButton(".",insert);  addButton("pow",cmd);  addButton("+",cmd);  addButton("sin",insert);  addButton("cos",insert);  addButton("tan",insert);  addButton("=",cmd);  add(panel, BorderLayout.CENTER); } private void addButton(String label,ActionListener listener) {  JButton button=new JButton(label);  button.addActionListener(listener);  panel.add(button); } private class InsertAction implements ActionListener {  public void actionPerformed(ActionEvent ae)  {   String input=ae.getActionCommand();   if(start==true)   {    display.setText("");    start=false;

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   }   if(input.equals("sin"))   {    Double angle=Double.parseDouble(display.getText())*2.0*Math.PI/360.0;    display.setText(""+Math.sin(angle));   }   else if(input.equals("cos"))   {    Double angle=Double.parseDouble(display.getText())*2.0*Math.PI/360.0;    display.setText(""+Math.cos(angle));   }   else if(input.equals("tan"))   {    Double angle=Double.parseDouble(display.getText())*2.0*Math.PI/360.0;    display.setText(""+Math.tan(angle));   }   else   display.setText(display.getText()+input);  } } private class CommandAction implements ActionListener {  public void actionPerformed(ActionEvent ae)  {   String command=ae.getActionCommand();   if(start==true)   {    if(command.equals("-"))    {     display.setText(command);     start=false;    }    else    lastcmd=command;   }   else   {    calc(Double.parseDouble(display.getText()));    lastcmd=command;    start=true;   }  } } public void calc(double x) {  if(lastcmd.equals("+"))  result=result+x;  else if(lastcmd.equals("-"))

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  result=result-x;  else if(lastcmd.equals("*"))  result=result*x;  else if(lastcmd.equals("/"))  result=result/x;  else if(lastcmd.equals("="))  result=x;  else if(lastcmd.equals("pow"))  {   double powval=1.0;   for(double i=0.0;i<x;i++)   powval=powval*result;   result=powval;  }  display.setText(""+ result); }}

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8. IMPLEMENTATION OF FIBONACCI SERIES USING FRAMES

Write a multi-threaded Java program to print all numbers below 100,000 that are both prime and fibonacci number (some examples are 2, 3, 5, 13, etc.). Design a thread that generates prime numbers below 100,000 and writes them into a pipe. Design another thread that generates fibonacci numbers and writes them to another pipe. The main thread should read both the pipes to identify numbers common to both.

ALGORITHM:STEP 1: CreateThread1 which generates prime numbers below 100,000 and store in pipe1.STEP 2: Create Thread2 which generates Fibonacci numbers below 100,000 and store in pipe 2.STEP 3: Write a main program which does the following:

(i) Call the two threads created in step1 and step2.(ii) Read the data from pipe1 and pipe 2 and print the numbers

common to both.

MultiThreadDemo.java

import java.util.*;import java.io.*;class Fibonacci extends Thread{ private PipedWriter out=new PipedWriter(); public PipedWriter getPipedWriter() {  return out; } public void run() {  Thread t=Thread.currentThread();  t.setName("Fibonacci");  System.out.println(t.getName()+" Thread started...");  int fibo=0,fibo1=0,fibo2=1;  while(true)  {   try   {    fibo=fibo1+fibo2;    if(fibo>100000)    {     out.close();     break;    }    out.write(fibo);    sleep(1000);     

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   }   catch(Exception e)   {    System.out.println("Exception:"+e);   }   fibo1=fibo2;   fibo2=fibo;  }  System.out.println(t.getName()+" Thread exiting..."); }}class Prime extends Thread{ private PipedWriter out1=new PipedWriter(); public PipedWriter getPipedWriter() {  return out1; } public void run() {  Thread t=Thread.currentThread();  t.setName("Prime");  System.out.println(t.getName() +" Thread Started...");  int prime=1;  while(true)  {   try   {    if(prime>100000)    {     out1.close();     break;    }    if(isPrime(prime))    out1.write(prime);    prime++;    sleep(0);   }   catch(Exception e)   {    System.out.println(t.getName()+" Thread exiting...");    System.exit(0);   }  } } public boolean isPrime(int n) {  int m=(int)Math.round(Math.sqrt(n));

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  if(n==1||n==2)  return true;  for(int i=2;i<=m;i++)  if(n%i==0)  return false;  return true; }}/****/

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8. IMPLEMENTATION OF FIBONACCI SERIES USING FRAMES

Develop a simple OPAC system for library using event-driven and concurrent programming paradigms of Java. Use JDBC to connect to a back-end database.

ALGORITHM:STEP 1: Create a Master Database1(Book Details) having the following fields: BookNo.Book Name, Author, No. of pages, Name of Publisher, Cost.STEP 2: Create a Master Database2(User Details) having the following fields : UserID, Department STEP 3: Create a Transaction Database having the following fields: UserID, Book No., Date of Renewal / Date of Return, FineSTEP 4: Create a panel consisting of buttons ADD, UPDATE, DELETE. Associate these button actions with listeners(with Master Database 1)STEP 5: Create a panel consisting of buttons ADD, UPDATE, DELETE. Associate these button actions with listeners(with Master Database 2)STEP 6: Create another panel consisting of buttons UserID, BookID, Return/Renewal,Fine.STEP 7: Associate these buttons with listeners(with Transaction Database).

OpacSystem.java

import java.sql.*;import java.awt.*;import java.awt.event.*;import javax.swing.*;import javax.swing.table.*;/****/public class OpacSystem implements ActionListener{ JRadioButton author=new JRadioButton("Search By Author"); JRadioButton book=new JRadioButton("Search by Book"); JTextField txt=new JTextField(30); JLabel label=new JLabel("Enter Search Key"); JButton search=new JButton("SEARCH"); JFrame frame=new JFrame(); JTable table; DefaultTableModel model; String query="select*from opacTab"; public OpacSystem() {  frame.setTitle("OPAC SYSTEM");  frame.setSize(800,500);  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  frame.setLayout(new BorderLayout());

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  JPanel p1=new JPanel();  p1.setLayout(new FlowLayout());  p1.add(label);  p1.add(txt);  ButtonGroup bg=new ButtonGroup();  bg.add(author);  bg.add(book);   JPanel p2=new JPanel();  p2.setLayout(new FlowLayout());  p2.add(author);  p2.add(book);  p2.add(search);  search.addActionListener(this);  JPanel p3=new JPanel();     p3.setLayout(new BorderLayout());  p3.add(p1,BorderLayout.NORTH);  p3.add(p2,BorderLayout.CENTER);  frame.add(p3,BorderLayout.NORTH);  addTable(query);  frame.setVisible(true); } public void addTable(String str) {  try  {   Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");   Connection con=DriverManager.getConnection("jdbc:odbc:opacDS");   Statement stmt=con.createStatement();   ResultSet rs=stmt.executeQuery(str);   ResultSetMetaData rsmd=rs.getMetaData();   int cols=rsmd.getColumnCount();   model=new DefaultTableModel(1,cols);   table=new JTable(model);   String[] tabledata=new String[cols];   int i=0;   while(i<cols)   {    tabledata[i]=rsmd.getColumnName(i+1);    i++;   }   model.addRow(tabledata);   while(rs.next())   {    for(i=0;i<cols;i++)    tabledata[i]=rs.getObject(i+1).toString();    model.addRow(tabledata);   }   frame.add(table,BorderLayout.CENTER);

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   con.close();  }  catch(Exception e)  {   System.out.println("Exception:"+e);  } } public void actionPerformed(ActionEvent ae) {  if(author.isSelected())  query="select*from opacTab where AUTHOR like '"+txt.getText()+"%'";  if(book.isSelected())  query="select*from opacTab where BOOK like '"+txt.getText()+"%'";  while(model.getRowCount()>0)  model.removeRow(0);  frame.remove(table);  addTable(query); }

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10. IMPLEMENTATION OF MULTITHREADEDECHO SERVER & ECHO CLIENT

Develop multi-threaded echo server and a corresponding GUI client in Java.

ALGORITHM FOR SERVER:STEP 1: Establish the connection of socket.STEP 2: Assign the local Protocol address to the socket.STEP 3: Move the socket from closed to listener state and provide maximum no. of Connections.STEP 4: Create a new socket connection using client address.STEP 5: Read the data from the socket.STEP 6: Write the data into socket.STEP 7: Close the socket.

EchoServer.java

import java.io.*;import java.net.*;/****/public class EchoServer{ public static void main(String [] args) {  System.out.println("Server Started....");  try  {   ServerSocket ss=new ServerSocket(300);   while(true)   {    Socket s= ss.accept();    Thread t = new ThreadedServer(s);    t.start();   }  }  catch(Exception e)  {   System.out.println("Error: " + e);  } }}class ThreadedServer extends Thread{ Socket soc; public ThreadedServer(Socket soc)

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 {  this.soc=soc; } public void run() {  try  {   BufferedReader in=new BufferedReader(new InputStreamReader(soc.getInputStream()));   PrintWriter out=new PrintWriter(soc.getOutputStream());   String str=in.readLine();   System.out.println("Message From Client:"+str);   out.flush();   out.println("Message To Client:"+str);   out.flush();  }  catch(Exception e)  {   System.out.println("Exception:"+e);  } }}

ALGORITHM FOR CLIENT:STEP 1: Open the socket.STEP 2: Get the host name and port number from client.STEP 3: Write a request to the buffer that contain the request number as a byte to the output stream.STEP 4: Get the message from the user.STEP 5: Write to the socket.STEP 6: Set the write operation for success.STEP 7: Read the contents from the socket / Buffer.STEP 8: Close the socket.

EchoClient.java

import java.net.*;import java.io.*;import javax.swing.*;import java.awt.*;import java.awt.event.*;/****/class EchoClient extends JFrame{

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 JTextArea ta; JTextField msg; JPanel panel; JScrollPane scroll; JButton b1=new JButton("Close"); JButton b2=new JButton("Send"); JLabel l1=new JLabel("Echo Client GUI"); Container c; EchoClient() {  c=getContentPane();  setSize(300,470);  setTitle("GUI Client");  panel=new JPanel();  msg=new JTextField(20);  panel.setLayout(new FlowLayout(FlowLayout.CENTER));  ta=new JTextArea(20,20);  scroll=new JScrollPane(ta);  panel.add(l1);  panel.add(ta);  panel.add(msg);  panel.add(b2);  panel.add(b1);  c.add(panel);  b2.addActionListener(new ActionListener()  {   public void actionPerformed(ActionEvent ae)   {    try    {     Socket s=new Socket("localhost",300);     BufferedReader in=new BufferedReader(new InputStreamReader(s.getInputStream()));     PrintWriter out=new PrintWriter(new OutputStreamWriter(s.getOutputStream()));     out.println(msg.getText());     out.flush();     String temp =ta.getText();     if(temp.equalsIgnoreCase("quit"))     {      System.exit(0);     }     msg.setText("");     ta.append("\n"+in.readLine());    }    catch (IOException e)    {     ta.setText("Exception:"+e);

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    }   }  });  b1.addActionListener(new ActionListener()  {   public void actionPerformed(ActionEvent e)   {    System.exit(0);   }  }); } public static void main(String args[]) {  EchoClient frame=new EchoClient();  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  frame.setVisible(true); }}

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11. MINI PROJECT

Develop a programmer's editor in Java that supports syntax high lighting, compilation support, debugging support, etc.

ALGORITHM:STEP 1: Create a panel consisting of menu bar containing File, Edit, Compile and Debug.STEP 2: Add submenus for each of the menu.

File – New, Open, Save, Quit. Edit – Cut, Copy, Paste.Compile – Compile, LinkDebug – Inspect, Call Stack, Watches, BreakPoints.

STEP 3: Associate these event sources with Listeners.

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