Important Java Programs 14s4h

0) { String s1=arr[i]; arr[i]=arr[j]; arr[j]=s1; }

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{

JAVA } } return arr; }

void display()throws ArrayIndexOutOfBoundsException { System.out.println ("Sorted list is---"); for (i=0;i
//end of the Test class

class Ascend { public static void main(String args[ ])throws IOException { Test obj1=new Test(4); obj1.getArray(); obj1.check(); obj1.display(); } }

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JAVA

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JAVA Program Statement :

WAJP to multiply two given matrices.

Program :

import java.util.*; class Test { int r1,c1,r2,c2;

Test(int r1,int c1,int r2,int c2) { this.r1=r1; this.c1=c1; this.r2=r2; this.c2=c2; }

int[ ][ ] getArray(int r,int c) { int arr[][]=new int[r][c]; System.out.println("Enter the elements for "+r+"X"+c+" Matrix:"); Scanner input=new Scanner(System.in);

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JAVA for(int i=0;i
int[ ][ ] findMul(int a[ ][ ],int b[ ][ ]) { int c[][]=new int[r1][c2]; for (int i=0;i
void putArray(int res[ ][ ]) { System.out.println ("The resultant "+r1+"X"+c2+" Matrix is:"); for (int i=0;i
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JAVA System.out.println(); } } } //end of Test class

class MatrixMul { public static void main(String args[ ])throws IOException { Test obj1=new Test(2,3,3,2); Test obj2=new Test(2,3,3,2);

int x[ ][ ],y[ ][ ],z[ ][ ];

System.out.println("MATRIX-1:"); x=obj1.getArray(2,3);

//to get the matrix from

System.out.println("MATRIX-2:"); y=obj2.getArray(3,2);

z=obj1.findMul(x,y); obj1.putArray(z);

//to perform the multiplication // to display the resultant matrix

} } MCA-III

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JAVA

Input & Output :

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JAVA

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JAVA

Program Statement :

WAJP that reads a line of integers and then displays each integer and the sum of all integers. (use StringTokenizer class)

Program :

// Using StringTokenizer class import java.lang.*; import java.util.*;

class tokendemo { public static void main(String args[ ]) { String s="10,20,30,40,50"; int sum=0;

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JAVA StringTokenizer a=new StringTokenizer(s,",",false); System.out.println("integers are "); while(a.hasMoreTokens()) { int b=Integer.parseInt(a.nextToken()); sum=sum+b; System.out.println(" "+b); } System.out.println("sum of integers is "+sum); } }

// Alternate solution using command line arguments

class Arguments { public static void main(String args[ ]) { int sum=0; int n=args.length; System.out.println("length is "+n);

int arr[]=new int[n]; for(int i=0;i
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JAVA

System.out.println("The enterd values are:"); for(int i=0;i
System.out.println("sum of enterd integers is:"); for(int i=0;i
Input & Output :

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JAVA

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WAJP that reads on file name from the , then displays information about whether the file exists, whether the file is readable, wheteher the file is writable, the type of file and the length of the file in bytes.

Program :

import java.io.File; class FileDemo { static void p(String s) { System.out.println(s); } public static void main(String args[ ]) { File f1 = new File(args[0]); p("File Name: " + f1.getName()); p("Path: " + f1.getPath()); p("Abs Path: " + f1.getAbsolutePath()); p("Parent: " + f1.getParent()); p(f1.exists() ? "exists" : "does not exist"); p(f1.canWrite() ? "is writeable" : "is not writeable"); p(f1.canRead() ? "is readable" : "is not readable"); p("is " + (f1.isDirectory() ? "" : "not" + " a directory")); p(f1.isFile() ? "is normal file" : "might be a named pipe"); p(f1.isAbsolute() ? "is absolute" : "is not absolute"); p("File last modified: " + f1.lastModified()); p("File size: " + f1.length() + " Bytes"); } }

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JAVA

Input & Output :

:

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WAJP that reads a file and displays the file on the screen, with a line number before each line.

Program :

import java.io.*; class LineNum{ public static void main(String args[]){ String thisline; for(int i=0;i<args.length;i++) { try{ LineNumberReader br=new LineNumberReader(new FileReader(args[i])); while((thisline=br.readLine())!=null) { System.out.println(br.getLineNumber()+"."+thisline); } }catch(IOException e){ System.out.println("error:"+e);

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JAVA } } } }

Input & Output :

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JAVA

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JAVA Program Statement : WAJP that displays the number of characters, lines and words in a text file.

Program :

import java.io.*; public class FileStat { public static void main(String args[ ])throws IOException { long nl=0,nw=0,nc=0; String line; BufferedReader br=new BufferedReader(new FileReader(args[0])); while ((line=br.readLine())!=null) { nl++; nc=nc+line.length(); int i=0; boolean pspace=true; while (i
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JAVA nw++; pspace=cspace; } } System.out.println("Number of Characters"+nc); System.out.println("Number of Characters"+nw); System.out.println("Number of Characters"+nl); }}

// Alternate solution using StringTokenizer import java.io.*; import java.util.*; public class FileStat { public static void main(String args[ ])throws IOException { long nl=0,nw=0,nc=0; String line; BufferedReader br=new BufferedReader(new FileReader(args[0])); while ((line=br.readLine())!=null) { nl++; nc=nc+line.length(); StringTokenizer st = new StringTokenizer(line);

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JAVA nw += st.countTokens(); } System.out.println("Number of Characters"+nc); System.out.println("Number of Characters"+nw); System.out.println("Number of Characters"+nl); }}

Input & Output :

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WAJP that: (a)

Implements a Stack ADT

(b)

Converts Infix expression to Postfix expression

(c)

Evaluates a Postfix expression

Program :

import java.io.*;

interface stack { void push(int item); int pop(); }

class Stackimpl { private int stck[]; private int top; MCA-III

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JAVA

Stackimpl(int size) { stck=new int[size]; top=-1; }

void push(int item) { if(top==stck.length-1) System.out.println("stack is full insertion is not possible");

else stck[++top]=item; }

int pop() { if(top==-1) {

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JAVA System.out.println("stack is empty deletion is not possible"); return 0; } else return stck[top--]; } }

class Stackdemo {

public static void main(String args[])throws IOException { int a[];

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

System.out.println("enter the size of the array"); int n=Integer.parseInt(br.readLine());

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JAVA

Stackimpl obj1=new Stackimpl(n);

a=new int[n];

System.out.println("enter numbers into the stack");

for(int i=0;i
System.out.println("numbers are inserted"); for(int i=0;i
System.out.println("The following numbers are poped out."); for(int i=0;i
} }

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JAVA Input & Output :

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Write an Applet that displays a simple message.

Program :

import java.awt.*; import java.applet.*;

/*

code = “HelloJava” width = 200

*/

public class HelloJava extends Applet { public void paint(Graphics g) { g.drawString(“Hello Java”, 10, 100); } }

Input & Output :

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height = 60 >

JAVA

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Write an Applet that computes the payment of a loan based on the amount of the loan, the interest rate and the number of months. It takes one parameter from the browser: Monthly rate; if true, the interest rate is per month, otherwise the interest rate is annual.

Program :

import java.awt.*; import java.awt.event.*; import java.applet.*;

/* <param name = monthlyRate value=true> */

public class LoanPayment extends Applet implements ActionListener { TextField amt_t, rate_t, period_t; Button compute = new Button("Compute"); boolean monthlyRate;

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JAVA

public void init() { Label amt_l = new Label("Amount: "); Label rate_l = new Label("Rate: ", Label.CENTER); Label period_l = new Label("Period: ", Label.RIGHT);

amt_t = new TextField(10); rate_t = new TextField(10); period_t = new TextField(10);

add(amt_l); add(amt_t); add(rate_l); add(rate_t); add(period_l); add(period_t); add(compute);

amt_t.setText("0"); rate_t.setText("0"); period_t.setText("0"); MCA-III

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JAVA

monthlyRate = Boolean.valueOf(getParameter("monthlyRate"));

amt_t.addActionListener(this); rate_t.addActionListener(this); period_t.addActionListener(this); compute.addActionListener(this); }

public void paint(Graphics g) { double amt=0, rate=0, period=0, payment=0; String amt_s, rate_s, period_s, payment_s;

g.drawString("Input the Loan Amt, Rate and Period in each box and press Compute", 50,100); try { amt_s = amt_t.getText(); amt = Double.parseDouble(amt_s); rate_s = rate_t.getText(); rate = Double.parseDouble(rate_s); period_s = period_t.getText();

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JAVA period = Double.parseDouble(period_s); } catch (Exception e) { }

if (monthlyRate) payment = amt * period * rate * 12 / 100; else payment = amt * period * rate / 100;

payment_s = String.valueOf(payment);

g.drawString("The LOAN PAYMENT amount is: ", 50, 150); g.drawString(payment_s, 250, 150); }

public void actionPerformed(ActionEvent ae) { repaint(); }

}

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JAVA

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WAJP that works as a simple calculator. Use a grid layout to arrange buttons for the digits and for the + - x / % operations. Add atext field to display the result. Program :

import javax.swing.*; import java.awt.*; import java.awt.event.*; // public class Calculator extends JApplet { public void init() { Calculator calc=new Calculator(); getContentPane().add(calc); } }

class Calculator extends J implements ActionListener { JButton n1,n2,n3,n4,n5,n6,n7,n8,n9,n0,plus,minus,mul,div,dot,equal; static JTextField result=new JTextField("0",45);

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JAVA static String lastCommand=null; JOptionPane p=new JOptionPane(); double preRes=0,secVal=0,res;

private static void assign(String no) { if((result.getText()).equals("0")) result.setText(no); else if(lastCommand=="=") { result.setText(no); lastCommand=null; } else result.setText(result.getText()+no); }

public Calculator() { setLayout(new BorderLayout()); result.setEditable(false); result.setSize(300,200); add(result,BorderLayout.NORTH); MCA-III

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JAVA J =new J(); .setLayout(new GridLayout(4,4));

n7=new JButton("7"); .add(n7); n7.addActionListener(this); n8=new JButton("8"); .add(n8); n8.addActionListener(this); n9=new JButton("9"); .add(n9); n9.addActionListener(this); div=new JButton("/"); .add(div); div.addActionListener(this);

n4=new JButton("4"); .add(n4); n4.addActionListener(this); n5=new JButton("5"); .add(n5); n5.addActionListener(this); MCA-III

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JAVA n6=new JButton("6"); .add(n6); n6.addActionListener(this); mul=new JButton("*"); .add(mul); mul.addActionListener(this);

n1=new JButton("1"); .add(n1); n1.addActionListener(this); n2=new JButton("2"); .add(n2); n2.addActionListener(this); n3=new JButton("3"); .add(n3); n3.addActionListener(this); minus=new JButton("-"); .add(minus); minus.addActionListener(this);

dot=new JButton("."); .add(dot); MCA-III

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JAVA dot.addActionListener(this); n0=new JButton("0"); .add(n0); n0.addActionListener(this); equal=new JButton("="); .add(equal); equal.addActionListener(this); plus=new JButton("+"); .add(plus); plus.addActionListener(this); add(,BorderLayout.CENTER); } public void actionPerformed(ActionEvent ae) { if(ae.getSource()==n1) assign("1"); else if(ae.getSource()==n2) assign("2"); else if(ae.getSource()==n3) assign("3"); else if(ae.getSource()==n4) assign("4"); else if(ae.getSource()==n5) assign("5"); else if(ae.getSource()==n6) assign("6"); else if(ae.getSource()==n7) assign("7"); else if(ae.getSource()==n8) assign("8"); MCA-III

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JAVA else if(ae.getSource()==n9) assign("9"); else if(ae.getSource()==n0) assign("0"); else if(ae.getSource()==dot) { if(((result.getText()).indexOf("."))==-1) result.setText(result.getText()+"."); } else if(ae.getSource()==minus) { preRes=Double.parseDouble(result.getText()); lastCommand="-"; result.setText("0"); } else if(ae.getSource()==div) { preRes=Double.parseDouble(result.getText()); lastCommand="/"; result.setText("0"); } else if(ae.getSource()==equal) { secVal=Double.parseDouble(result.getText()); MCA-III

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JAVA if(lastCommand.equals("/")) res=preRes/secVal; else if(lastCommand.equals("*")) res=preRes*secVal; else if(lastCommand.equals("-")) res=preRes-secVal; else if(lastCommand.equals("+")) res=preRes+secVal; result.setText(" "+res); lastCommand="="; } else if(ae.getSource()==mul) { preRes=Double.parseDouble(result.getText()); lastCommand="*"; result.setText("0"); } else if(ae.getSource()==plus) { preRes=Double.parseDouble(result.getText()); lastCommand="+"; result.setText("0"); MCA-III

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JAVA } } } Input & Output :

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WAJP for handling mouse events.

Program :

import java.awt.*; import java.awt.event.*; import java.applet.*; /* */ public class MouseEvents extends Applet implements MouseListener, MouseMotionListener { String msg = ""; int mouseX = 0, mouseY = 0; // coordinates of mouse public void init() { addMouseListener(this); addMouseMotionListener(this); } // Handle mouse clicked. public void mouseClicked(MouseEvent me) { // save coordinates mouseX = 0; mouseY = 10; msg = "Mouse clicked."; repaint(); } // Handle mouse entered. MCA-III

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JAVA public void mouseEntered(MouseEvent me) { // save coordinates mouseX = 0; mouseY = 10; msg = "Mouse entered."; repaint(); } // Handle mouse exited. public void mouseExited(MouseEvent me) { // save coordinates mouseX = 0; mouseY = 10; msg = "Mouse exited."; repaint(); } // Handle button pressed. public void mousePressed(MouseEvent me) { // save coordinates mouseX = me.getX(); mouseY = me.getY(); msg = "Down"; repaint(); } // Handle button released. public void moeleased(MouseEvent me) { // save coordinates mouseX = me.getX(); mouseY = me.getY(); msg = "Up"; repaint(); } // Handle mouse dragged. public void mouseDragged(MouseEvent me) { // save coordinates mouseX = me.getX(); mouseY = me.getY(); MCA-III

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JAVA msg = "*"; showStatus("Dragging mouse at " + mouseX + ", " + mouseY); repaint(); } // Handle mouse moved. public void mouseMoved(MouseEvent me) { // show status showStatus("Moving mouse at " + me.getX() + ", " + me.getY()); } // Display msg in applet window at current X,Y location. public void paint(Graphics g) { g.drawString(msg, mouseX, mouseY); } } Input & Output :

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JAVA

Program Statement :

WAJP for creating multiple threads.

Program :

class NewThread implements Runnable { String name; // name of thread Thread t; NewThread(String threadname) { name = threadname;

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JAVA t = new Thread(this, name); System.out.println("New thread: " + t); t.start(); // Start the thread } // This is the entry point for thread. public void run() { try { for(int i = 5; i > 0; i--) { System.out.println(name + ": " + i); Thread.sleep(1000); } } catch (InterruptedException e) { System.out.println(name + "Interrupted"); } System.out.println(name + " exiting."); } } class MultiThreadDemo { public static void main(String args[]) { new NewThread("One"); // start threads new NewThread("Two"); new NewThread("Three"); try { // wait for other threads to end Thread.sleep(10000); } catch (InterruptedException e) { System.out.println("Main thread Interrupted"); } System.out.println("Main thread exiting."); } }

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JAVA

Input & Output :

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JAVA

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WAJP that correctly implements Producer-Consumer problem using the concept of Inter Thread Communication.

Program :

class Q { int n; boolean valueSet = false;

synchronized int get() { if (!valueSet) try { wait(); } catch (InterruptedException e) { }

System.out.println(“Got: “ + n); valueSet = false; notify(); return n; }

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JAVA

synchronized void put(int n) { if (valueSet) try { wait(); } catch (InterruptedException e) { }

this.n = n; valueSet = true; System.out.println(“Put: “ + n); notify(); } }

class Producer implements Runnable { Q q;

Producer(Q q) { this.q = q; new Thread(this, “Producer”).start(); }

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JAVA public void run() { int i = 0;

while(true) { q.put(i++); } } }

class Consumer implements Runnable { Q q;

Consumer(Q q) { this.q = q; new Thread(this, “Consumer”).start(); }

public void run() { while(true) { q.get(); } } MCA-III

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JAVA }

class PC { public static void main (String args[ ]) { Q q = new Q(); new Producer(q); new Consumer(q);

System.out.println(“Press Ctrl-C to stop”); } }

Input & Output :

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JAVA

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WAJP that lets s create Pie charts. Design your own interface (with Swings & AWT).

Program :


/* */

public class PiChart extends Applet { public void paint(Graphics g)

{

setBackground(Color.green); g.drawString("PI CHART",200,40);

g.setColor(Color.blue); g.fillOval(50,50,150,150); g.setColor(Color.white); g.drawString("40%",130,160); g.setColor(Color.magenta);

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JAVA g.fillArc(50,50,150,150,0,90); g.setColor(Color.white); g.drawString("25%",140,100); g.setColor(Color.yellow); g.fillArc(50,50,150,150,90,120); g.setColor(Color.black); g.drawString("35%",90,100);

g.setColor(Color.yellow); g.fillOval(250,50,150,150); g.setColor(Color.black); g.drawString("15%",350,150); g.setColor(Color.magenta); g.fillArc(250,50,150,150,0,30); g.setColor(Color.black); g.drawString("5%",360,120); g.setColor(Color.blue); g.fillArc(250,50,150,150,30,120); g.setColor(Color.white); g.drawString("30%",330,100); g.setColor(Color.black); g.fillArc(250,50,150,150,120,180); MCA-III

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JAVA g.setColor(Color.white); g.drawString("50%",280,160); } }

Input & Output :

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JAVA

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JAVA Program Statement : WAJP that allows to draw lines, rectangles and ovals.

Program : import javax.swing.*; import java.awt.Graphics;

public class choice extends JApplet { int i,ch; public void init() { String input; input=JOptionPane.showInputDialog("enter choice(1-lines,2-rectangles,3-ovals)"); ch=Integer.parseInt(input); } public void paint(Graphics g) { switch(ch) { case 1:{

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your

JAVA for(i=1;i<=10;i++) { g.drawLine(10,10,250,10*i); } break; }

case 2:{ for(i=1;i<=10;i++) { g.drawRect(10*i,10*i,50+10*i,50+10*i); } break; }

case 3:{ for(i=1;i<=10;i++) { g.drawOval(10*i,10*i,50+10*i,50+10*i); } break; }}}} MCA-III

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JAVA

Input & Output :

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JAVA

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WAJP that implements a simple client/server application. The client sends data to a server. The server receives the data, uses it to produce a result and then sends the result back to the client. The client displays the result on the console. For ex: The data sent from the client is the radius of a circle and the result produced by the server is the area of the circle.

Program :

// Server Program import java.io.*; import java.net.*; import java.util.*;

public class Server { public void static main (String args [ ] ) { try { // create a server socket ServerSocket s = new ServerSocket(8000);

// start listening for connections on srver socket

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JAVA Socket connectToClient = s.accept();

// create a buffered reader stream to get data from client BufferedReader isFromClient = new BufferedReader(new InputStreamReader (connectToClient.getInputStream()));

// create a buffer reader to send result to client PrintWriter osToClient = new PrintWriter(connectToClient.getOutputStream(), true);

// continuously read from client, process, send back while (true) { // read a line and create string tokenizer StringTokenizer st = new StringTokenizer(isFromClient.readLine());

//convert string to double double radius = new Double(st.nextToken()).doubleValue();

// display radius on console

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JAVA System.out.println(“Radius received from client: “ + radius);

// comput area double area = radius * radius *Math.PI;

// send result to client osToClient.println(area);

// print result on console System.out.println(“Area found: “ +area); } } catch (IOException e) { System.err.println(e); } } }

// Client Program import java.io.*;

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JAVA import java.net.*; import java.util.*;

public class Client { public void static main (String args [ ] ) { try { // create a socket to connect to server Socket connectToServer = new Socket(“local host”, 8000);

// create a buffered input stream to get result from server BufferedReader isFromServer = new BufferedReader(new InputStreamReader (connectToServer.getInputStream()));

// create a buffer output stream to send data to server PrintWriter osToServer = new PrintWriter(connectToClient.getOutputStream(), true);

// continuously send radius and get area while (true) { Scanner input=new Scanner(System.in); MCA-III

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JAVA System.out.print(“Please enter a radius: “); double radius =input.nextDouble();

// display radius on console osToServer.println(radius);

// get area from server StringTokenizer st = new StringTokenizer(isFromServer.readLine());

// convert string to double Double area = new Double(st.nextToken()).doubleValue();

// print result on console System.out.println(“Area received from the server is: “ +area); } } catch (IOException e) { System.err.println(e); } } } MCA-III

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JAVA

Input & Output :

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JAVA

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WAJP that illustrates how runtime polymorphism is achieved.

Program :

class Figure { double dim1; double dim2; Figure(double a, double b) { dim1 = a; dim2 = b; } double area() { System.out.println("Area for Figure is undefined."); return 0; } } class Rectangle extends Figure { Rectangle(double a, double b) { super(a, b); } // override area for rectangle double area() { System.out.println("Inside Area for Rectangle."); return dim1 * dim2; } } class Triangle extends Figure { Triangle(double a, double b) { MCA-III

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JAVA super(a, b); } // override area for right triangle double area() { System.out.println("Inside Area for Triangle."); return dim1 * dim2 / 2; } } class FindAreas { public static void main(String args[]) { Figure f = new Figure(10, 10); Rectangle r = new Rectangle(9, 5); Triangle t = new Triangle(10, 8); Figure figref; figref = r; System.out.println("Area is " + figref.area()); figref = t; System.out.println("Area is " + figref.area()); figref = f; System.out.println("Area is " + figref.area()); } }

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JAVA

Input & Output :

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JAVA Program Statement : WAJP to generate a set of random numbers. Find its sum and average. The program should also display ‘*’ based on the random numbers generated.

Program :

import java.util.*; class RandNum { public static void main(String ax[ ]) { int a[ ]=new int[5]; int sum=0; Random r=new Random(); for (int i=0;i<5;i++) { a[i]=r.nextInt(10); System.out.print(a[i]); for(int y=0;y
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JAVA

System.out.println("Sum="+sum); System.out.println("Avg="+(double)sum/a.length); } }

Input & Output :

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JAVA

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JAVA

Program Statement :

WAJP to create an abstract class named Shape, that contains an empty method named numberOfSides(). Provide three classes named Trapezoid, Triangle and Hexagon, such that each one of the classes contains only the method numberOfSides(), that contains the number of sides in the given geometrical figure.

Program :

abstract class Shape { abstract void numberOfSides(); } class Trapezoid extends Shape{

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JAVA void numberOfSides() { System.out.println(" Trapezoidal has four sides"); } } class Triangle extends Shape { void numberOfSides() { System.out.println("Triangle has three sides"); } } class Hexagon extends Shape { void numberOfSides() { System.out.println("Hexagon has six sides"); } } class ShapeDemo { public static void main(String args[ ]) { Trapezoid t=new Trapezoid(); Triangle r=new Triangle(); Hexagon h=new Hexagon(); Shape s; MCA-III

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JAVA s=t; s.numberOfSides(); s=r; s.numberOfSides(); s=h; s.numberOfSides(); } }

Input & Output :

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WAJP to implement a Queue, using defined Exception Handling (also make use of throw, throws).

Program :

import java.util.Scanner;

class ExcQueue extends Exception { ExcQueue(String s)

{

super(s); } }

class Queue { int front,rear; int q[ ]=new int[10];

Queue() { rear=-1; front=-1;

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JAVA }

void enqueue(int n) throws ExcQueue { if (rear==9) throw new ExcQueue("Queue is full"); rear++; q[rear]=n; if (front==-1) front=0; }

int dequeue() throws ExcQueue { if (front==-1) throw new ExcQueue("Queue is empty"); int temp=q[front]; if (front==rear) front=rear=-1; else front++; return(temp); } } MCA-III

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JAVA

class UseQueue { public static void main(String args[ ]) { Queue a=new Queue(); try { a.enqueue(5); a.enqueue(20); } catch (ExcQueue e) { System.out.println(e.getMessage()); } try { System.out.println(a.dequeue()); System.out.println(a.dequeue()); System.out.println(a.dequeue()); } catch(ExcQueue e) { System.out.println(e.getMessage()); } } }

Input & Output :

MCA-III

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JAVA

MCA-III

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WAJP that creates 3 threads by extending Thread class. First thread displays “Good Morning” every 1 sec, the second thread displays “Hello” every 2 seconds and the third displays “Welcome” every 3 seconds. (Repeat the same by implementing Runnable)

Program :

// Using Thread class class One extends Thread { public void run() { for ( ; ; ) { try{ sleep(1000); }catch(InterruptedException e){} System.out.println("Good Morning"); } } }

class Two extends Thread { public void run() MCA-III

{ Page 110

JAVA for ( ; ; ) { try{ sleep(2000); }catch(InterruptedException e){} System.out.println("Hello"); } } }

class Three extends Thread { public void run() { for ( ; ; ) { try{ sleep(3000); }catch(InterruptedException e){} System.out.println("Welcome"); } } }

class MyThread { public static void main(String args[ ]) { MCA-III

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JAVA Thread t = new Thread(); One obj1=new One(); Two obj2=new Two(); Three obj3=new Three(); Thread t1=new Thread(obj1); Thread t2=new Thread(obj2); Thread t3=new Thread(obj3);

t1.start(); try{ t.sleep(1000); }catch(InterruptedException e){} t2.start(); try{ t.sleep(2000); }catch(InterruptedException e){} t3.start(); try{ t.sleep(3000); }catch(InterruptedException e){}

} MCA-III

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JAVA }

// Using Runnable interface class One implements Runnable {

One( ) { new Thread(this, "One").start(); try{ Thread.sleep(1000); }catch(InterruptedException e){} }

public void run() { for ( ; ; ) { try{ Thread.sleep(1000); }catch(InterruptedException e){} System.out.println("Good Morning"); } } }

MCA-III

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JAVA class Two implements Runnable {

Two( ) { new Thread(this, "Two").start(); try{ Thread.sleep(2000); }catch(InterruptedException e){} }

public void run()

{

for ( ; ; ) { try{ Thread.sleep(2000); }catch(InterruptedException e){} System.out.println("Hello"); } } }

class Three implements Runnable {

Three( ) { MCA-III

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JAVA new Thread(this, "Three").start(); try{ Thread.sleep(3000); }catch(InterruptedException e){} }

public void run() { for ( ; ; ) { try{ Thread.sleep(3000); }catch(InterruptedException e){} System.out.println("Welcome"); } } }

class MyThread { public static void main(String args[ ]) { One obj1=new One(); Two obj2=new Two(); Three obj3=new Three(); } MCA-III

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JAVA }

Input & Output :

MCA-III

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WAJP that will compute the following series: (a)

1 + 1/2 + 1/3+ …….+ 1/n

(b)

1 + 1/2 + 1/ 22 + 1/ 23 + … … + 1/ 2n

(c)

ex = 1 + x/1! + x2/2! + x3/3! + … …

Program :

// (a)

1 + 1/2 + 1/3+ …….+ 1/n

import java.util.Scanner; class Series1 { public static void main(String arg[ ]) { int n; double sum=0,i; Scanner input= new Scanner(System.in); System.out.println("enter value of n:"); n=input.nextInt(); for(i=1;i<=n;i++) sum=sum+(double)(1/i);

System.out.println("Result:"+sum); MCA-III

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JAVA } }

Input & Output :

// (b)1 + 1/2 + 1/ 22 + 1/ 23 + … … + 1/ 2n

import java.util.Scanner; class Series2 { public static void main(String arg[ ]) { int n; double sum=0,i; Scanner input= new Scanner(System.in); System.out.println("enter value of n:"); n=input.nextInt();

MCA-III

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JAVA for(i=1;i<=n;i++) sum=sum+(double)(1/Math.pow(2,i-1));

System.out.println("Result:"+sum); } }

Input & Output :

MCA-III

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JAVA

// (c) ex = 1 + x/1! + x2/2! + x3/3! + … …

import java.util.*; class Series3{ public static void main(String arg[ ]) { int n,x; double sum=0,i,d=1; Scanner input= new Scanner(System.in); System.out.println("enter value of n:"); n=input.nextInt(); System.out.println("enter value of x:"); x=input.nextInt(); for (i=1;i<=n;i++) { sum=sum+(double)((Math.pow(x,i-1)/d)); d=d*i; } System.out.println("Result :"+sum); } } MCA-III

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JAVA

Input & Output :

MCA-III

Page 121


WAJP to do the following: (a)

To output the question “Who is the inventor of Java?”

(b)

To accept an answer

(c)

To printout “GOOD” and then stop if the answer is correct

(d) wrong

To output the message “TRY AGAIN”, if the answer is

(e) To display the correct answer, when the answer is wrong even at the third attempt

Program :

import java.io.*; class Ask { public static void main(String a[ ])throws Exception { String str1,str2; int count=0; str1="James Gosling"; BufferedReader br=new BufferedReader(new InputStreamReader(System.in)); System.out.println("Who is the inventor of Java ?"); while(count!=3) { MCA-III

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JAVA str2=br.readLine(); if(str1.equalsIgnoreCase(str2)) { System.out.println("!!! GOOD !!!"); break; } else { if(count<2) System.out.println("TRY AGAIN !"); count++; } } if(count==3) System.out.println("Correct Answer is : "+str1); } }

Input & Output :

MCA-III

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JAVA

:

MCA-III

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WAJP to transpose a matrix using ‘arraycopy’ command.

Program :

class TransMatrix { public static void main(string args[ ]) { int i,j,k=0; int rows,cols,r,c; int a[ ][ ]={{1,2,3,4},{5,6,7,8}};

rows=a.length; cols=a[0].length; int b[ ][ ]=new int[rows*cols]; int s[ ]=new int[rows*cols]; int d[ ]=new int[rows*cols];

for (i=0;i
Page 125

JAVA while(r
System.out.println("a matrix:"); for (i=0;i
System.out.println("\nb matrix:"); for(i=0;i
Page 126

JAVA System.out.println(); } } }

Input & Output :

INPUT :

OUTPUT :

MCA-III

Page 127


Create an inheritance hierarchy of Rodent, Mouse, Gerbil, Hamster etc. In the base class provide methods that are common to all Rodents and override these in the derived classes to perform different behaviors, depending on the specific type of Rodent. Create an array of Rodent, fill it with different specific types of Rodents and call your base class methods.

Program :

import java.util.Random; class Rodent{ void place() {} void tail() {} void eat() {} public static Rodent randRodent(){ Random rr=new Random();

switch (rr.nextInt(4)) { case 0: return new Mouse(); case 1: return new Gerbil (); case 2: return new Hamster ();

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JAVA case 3: return new Beaver (); } return new Rodent(); } }

class Mouse extends Rodent { void place() { System.out.println(“Mice are found all over the world”); } void tail() { System.out.println(“Mice have long and hairless tail”); } void eat() { System.out.println(“Mice eat cardboards, papers, clothes”); } }

class Gerbil extends Rodent { void place() { MCA-III

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JAVA System.out.println(“Gerbils are found in arid parts of Africa and Asia”); } void tail() { System.out.println(“Gerbils have long tail”); } void eat() { System.out.println(“Gerbils eat seeds, roots, insects, parts of plants”); } }

class Hamster extends Rodent { void place() { System.out.println(“Hamsters are found in Western Europe to China – Dry regions only”); } void tail() { System.out.println(“Hamsters have short tail”); } void eat() { System.out.println(“Hamsters eat cereals”); } MCA-III

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JAVA }

class Beaver extends Rodent { void place() { System.out.println(“Beavers are found in Northern Europe and North America”); } void tail() { System.out.println(“Beavers have broad tail”); } void eat() { System.out.println(“Beavers eat bark”); } }

public class Rodents{ public static void main(String args[ ]) { Rodent r[] = new Rodent[6]; for (int i=0; i
for (int i=0; i
MCA-III

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JAVA r[i].place(); r[i].tail(); r[i].eat(); } } }

MCA-III

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JAVA

Input & Output :

MCA-III

Page 133


WAJP to print a chessboard pattern.

Program :


public class ChessBoard extends Applet { /* This applet draws a red-and-black checkerboard. It is assumed that the size of the applet is 160 by 160 pixels. */ /*

*/

public void paint(Graphics g) {

int row; // Row number, from 0 to 7 int col; // Column number, from 0 to 7 int x,y; // Top-left corner of square MCA-III

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JAVA

for ( row = 0; row < 8; row++ ) { for ( col = 0; col < 8; col++) { x = col * 40; y = row * 40; if ( (row % 2) == (col % 2) ) g.setColor(Color.white); else g.setColor(Color.black); g.fillRect(x, y, 40, 40); } } // end for row } // end paint() } // end class

Input & Output :

MCA-III

Page 135

JAVA

MCA-III

Page 136

JAVA SOME OTHER PROGRAMS APPLET PROGRAMS 1. // Demonstrate BorderLayout. import java.awt.*; import java.applet.*; import java.util.*; /* */

public class BorderLayoutDemo extends Applet { public void init() { setLayout(new BorderLayout());

add(new Button("This is across the top."), BorderLayout.NORTH); add(new Label("The footer message might go here."), BorderLayout.SOUTH); add(new Button("Right"), BorderLayout.EAST); add(new Button("Left"), BorderLayout.WEST);

MCA-III

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JAVA

String msg = "The reasonable man adapts " + "himself to the world;\n" + "the unreasonable one persists in " + "trying to adapt the world to himself.\n" + "Therefore all progress depends " + "on the unreasonable man.\n\n" + "

- George Bernard Shaw\n\n";

add(new TextArea(msg), BorderLayout.CENTER); } } 2. // Demonstrate Buttons import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

MCA-III

Page 138

JAVA public class ButtonDemo extends Applet implements ActionListener { String msg = ""; Button yes, no, maybe; TextField f1;

public void init() { yes = new Button("Yes"); no = new Button("No"); maybe = new Button("Undecided"); f1=new TextField(19); add(yes); add(no); add(maybe); add(f1); yes.addActionListener(this); no.addActionListener(this); maybe.addActionListener(this); }

public void actionPerformed(ActionEvent ae) { String str = ae.getActionCommand();

MCA-III

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JAVA

if(str.equals("Yes")) { msg = "You pressed Yes."; f1.setText(str); } else if(str.equals("No")) { msg = "You pressed No."; } else { msg = "You pressed Undecided."; } repaint(); }

public void paint(Graphics g) { g.drawString(msg, 6, 100); } }

3. // Demonstrate Buttons

MCA-III

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JAVA import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

public class ButtonDemo1 extends Frame implements ActionListener { static

String msg = "";

static Button yes, no, maybe;

public void ButtonDemo1() { yes = new Button("Yes"); no = new Button("No"); maybe = new Button("Undecided");

add(no); add(maybe);

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JAVA yes.addActionListener(this); no.addActionListener(this); maybe.addActionListener(this); }

public void actionPerformed(ActionEvent ae) { String str = ae.getActionCommand(); if(str.equals("Yes")) { msg = "You pressed Yes."; } else if(str.equals("No")) { msg = "You pressed No."; } else { msg = "You pressed Undecided."; }

}

public static void main(String s[]) { ButtonDemo1 b1=new ButtonDemo1(); b1.setSize(300,300); MCA-III

Page 142

JAVA b1.setVisible(true); b1.add(yes); b1.add(no); b1.add(maybe); System.out.println(msg);

} } 4. // Demonstrate CardLayout. import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

public class CardLayoutDemo extends Applet implements ActionListener, MouseListener {

Checkbox Win98, winNT, solaris, mac; MCA-III

Page 143

JAVA osCards; CardLayout cardLO; Button Win, Other;

public void init() { Win = new Button("Windows"); Other = new Button("Other"); add(Win); add(Other);

cardLO = new CardLayout(); osCards = new (); osCards.setLayout(cardLO); // set layout to card layout

Win98 = new Checkbox("Windows 98", null, true); winNT = new Checkbox("Windows NT"); solaris = new Checkbox("Solaris"); mac = new Checkbox("MacOS");

// add Windows check boxes to a winPan = new (); winPan.add(Win98); MCA-III

Page 144

JAVA winPan.add(winNT);

// Add other OS check boxes to a otherPan = new (); otherPan.add(solaris); otherPan.add(mac);

// add s to card deck osCards.add(winPan, "Windows"); osCards.add(otherPan, "Other");

// add cards to main applet add(osCards);

// to receive action events Win.addActionListener(this); Other.addActionListener(this);

// mouse events addMouseListener(this); }

MCA-III

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JAVA // Cycle through s. public void mousePressed(MouseEvent me) { cardLO.next(osCards); }

// Provide empty implementations for the other MouseListener methods. public void mouseClicked(MouseEvent me) { } public void mouseEntered(MouseEvent me) { } public void mouseExited(MouseEvent me) { } public void moeleased(MouseEvent me) { }

public void actionPerformed(ActionEvent ae) { if(ae.getSource() == Win) { cardLO.show(osCards, "Windows"); } else { cardLO.show(osCards, "Other");

MCA-III

Page 146

JAVA } } } 5. // Demonstrate check box group. import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

public class CBGroup extends Applet implements ItemListener { String msg = ""; Checkbox Win98, winNT, solaris, mac; CheckboxGroup cbg;

public void init() { cbg = new CheckboxGroup(); Win98 = new Checkbox("Windows 98", cbg, true); winNT = new Checkbox("Windows NT", cbg, false); solaris = new Checkbox("Solaris", cbg, false); MCA-III

Page 147

JAVA mac = new Checkbox("MacOS", cbg, false);

add(Win98); add(winNT); add(solaris); add(mac);

Win98.addItemListener(this); winNT.addItemListener(this); solaris.addItemListener(this); mac.addItemListener(this); }

public void itemStateChanged(ItemEvent ie) { repaint(); }

// Display current state of the check boxes. public void paint(Graphics g) { msg = "Current selection: "; msg += cbg.getSelectedCheckbox().getLabel(); g.drawString(msg, 6, 100); MCA-III

Page 148

JAVA } } 6. // Demonstrate check boxes. import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

public class CheckboxDemo extends Applet implements ItemListener { String msg = ""; Checkbox Win98, winNT, solaris, mac;

public void init() { Win98 = new Checkbox("Windows 98", null, true); winNT = new Checkbox("Windows NT"); solaris = new Checkbox("Solaris"); mac = new Checkbox("MacOS");

MCA-III

Page 149

JAVA add(Win98); add(winNT); add(solaris); add(mac);

Win98.addItemListener(this); winNT.addItemListener(this); solaris.addItemListener(this); mac.addItemListener(this); }


// Display current state of the check boxes. public void paint(Graphics g) { msg = "Current state: "; g.drawString(msg, 6, 80); msg = " Windows 98: " + Win98.getState(); g.drawString(msg, 6, 100); msg = " Windows NT: " + winNT.getState(); MCA-III

Page 150

JAVA g.drawString(msg, 6, 120); msg = " Solaris: " + solaris.getState(); g.drawString(msg, 6, 140); msg = " MacOS: " + mac.getState(); g.drawString(msg, 6, 160); } } 7. // Demonstrate Choice lists. import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

public class ChoiceDemo extends Applet implements ItemListener { Choice os, browser; String msg = "";

public void init() {

MCA-III

Page 151

JAVA os = new Choice(); browser = new Choice();

// add items to os list os.add("Windows 98"); os.add("Windows NT"); os.add("Solaris"); os.add("MacOS");

// add items to browser list browser.add("Netscape 1.1"); browser.add("Netscape 2.x"); browser.add("Netscape 3.x"); browser.add("Netscape 4.x");

browser.add("Internet Explorer 2.0"); browser.add("Internet Explorer 3.0"); browser.add("Internet Explorer 4.0");

browser.add("Lynx 2.4");

browser.select("Netscape 4.x"); MCA-III

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JAVA

// add choice lists to window add(os); add(browser);

// to receive item events os.addItemListener(this); browser.addItemListener(this); }


// Display current selections. public void paint(Graphics g) { msg = "Current OS: "; msg += os.getSelectedItem(); g.drawString(msg, 6, 120); msg = "Current Browser: "; msg += browser.getSelectedItem(); g.drawString(msg, 6, 140); MCA-III

Page 153

JAVA } } 8. import java.applet.Applet; import java.awt.*; /* */

// Create frame window. public class DialogDemo extends Applet { Frame f;

public void init() { f = new MenuFrame("Menu Demo"); int width = Integer.parseInt(getParameter("width")); int height = Integer.parseInt(getParameter("height"));

setSize(width, height);

f.setSize(width, height); f.setVisible(true); MCA-III

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JAVA }

public void start() { f.setVisible(true); }

public void stop() { f.setVisible(false); } } 9. // Use left-aligned flow layout. import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

public class FlowLayoutDemo extends Applet implements ItemListener {

MCA-III

Page 155

JAVA String msg = ""; Checkbox Win98, winNT, solaris, mac;

public void init() { // set left-aligned flow layout setLayout(new FlowLayout(FlowLayout.LEFT));

Win98 = new Checkbox("Windows 98", null, true); winNT = new Checkbox("Windows NT"); solaris = new Checkbox("Solaris"); mac = new Checkbox("MacOS");

add(Win98); add(winNT); add(solaris); add(mac);

// to receive item events Win98.addItemListener(this); winNT.addItemListener(this); solaris.addItemListener(this); mac.addItemListener(this); MCA-III

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JAVA }

// Repaint when status of a check box changes. public void itemStateChanged(ItemEvent ie) { repaint(); }

// Display current state of the checkboxes. public void paint(Graphics g) { msg = "Current state: "; g.drawString(msg, 6, 80); msg = " Windows 98: " + Win98.getState(); g.drawString(msg, 6, 100); msg = " Windows NT: " + winNT.getState(); g.drawString(msg, 6, 120); msg = " Solaris: " + solaris.getState(); g.drawString(msg, 6, 140); msg = " Mac: " + mac.getState(); g.drawString(msg, 6, 160); } }

MCA-III

Page 157

JAVA 10. // Demonstrate GridLayout import java.awt.*; import java.applet.*; /* */

public class GridLayoutDemo extends Applet { static final int n = 4; public void init() { setLayout(new GridLayout(n, n));

setFont(new Font("SansSerif", Font.BOLD, 24));

for(int i = 0; i < n; i++) { for(int j = 0; j < n; j++) { int k = i * n + j; if(k > 0) add(new Button("" + k)); } } MCA-III

Page 158

JAVA } } 11. // Demonstrate BorderLayout with insets. import java.awt.*; import java.applet.*; import java.util.*; /* */

public class InsetsDemo extends Applet { public void init() { // set background color so insets can be easily seen setBackground(Color.cyan);

setLayout(new BorderLayout());

add(new Button("This is across the top."), BorderLayout.NORTH); add(new Label("The footer message might go here."), BorderLayout.SOUTH); MCA-III

Page 159

JAVA add(new Button("Right"), BorderLayout.EAST); add(new Button("Left"), BorderLayout.WEST);

String msg = "The reasonable man adapts " + "himself to the world;\n" + "the unreasonable one persists in " + "trying to adapt the world to himself.\n" + "Therefore all progress depends " + "on the unreasonable man.\n\n" + "

- George Bernard Shaw\n\n";

add(new TextArea(msg), BorderLayout.CENTER); }

// add insets public Insets getInsets() { return new Insets(10, 10, 10, 10); } } 12. // Demonstrate Lists. import java.awt.*; import java.awt.event.*; MCA-III

Page 160

JAVA import java.applet.*; /* */

public class ListDemo extends Applet implements ActionListener { List os, browser; String msg = "";

public void init() { os = new List(4, true); browser = new List(4, false);

// add items to os list os.add("Windows 98"); os.add("Windows NT"); os.add("Solaris"); os.add("MacOS");

// add items to browser list browser.add("Netscape 1.1"); MCA-III

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JAVA browser.add("Netscape 2.x"); browser.add("Netscape 3.x"); browser.add("Netscape 4.x");

browser.add("Internet Explorer 2.0"); browser.add("Internet Explorer 3.0"); browser.add("Internet Explorer 4.0");

browser.add("Lynx 2.4");

browser.select(1);

// add lists to window add(os); add(browser);

// to receive action events os.addActionListener(this); browser.addActionListener(this); }

public void actionPerformed(ActionEvent ae) { MCA-III

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JAVA repaint(); }

// Display current selections. public void paint(Graphics g) { int idx[];

msg = "Current OS: "; idx = os.getSelectedIndexes(); for(int i=0; i
Page 163

JAVA /* */ public void init() { f = new MenuFrame("Menu Demo"); int width = Integer.parseInt(getParameter("width")); int height = Integer.parseInt(getParameter("height"));

setSize(new Dimension(width, height));

f.setSize(width, height); f.setVisible(true); }


public void stop() { f.setVisible(false); } } 14. // Illustrate menus. MCA-III

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JAVA import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

// Create a subclass of Frame class MenuFrame extends Frame { String msg = ""; CheckboxMenuItem debug, test;

MenuFrame(String title) { super(title);

// create menu bar and add it to frame MenuBar mbar = new MenuBar(); setMenuBar(mbar);

// create the menu items Menu file = new Menu("File"); MCA-III

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JAVA MenuItem item1, item2, item3, item4, item5; file.add(item1 = new MenuItem("New...")); file.add(item2 = new MenuItem("Open...")); file.add(item3 = new MenuItem("Close")); file.add(item4 = new MenuItem("-")); file.add(item5 = new MenuItem("Quit...")); mbar.add(file);

Menu edit = new Menu("Edit"); MenuItem item6, item7, item8, item9; edit.add(item6 = new MenuItem("Cut")); edit.add(item7 = new MenuItem("Copy")); edit.add(item8 = new MenuItem("Paste")); edit.add(item9 = new MenuItem("-")); Menu sub = new Menu("Special"); MenuItem item10, item11, item12; sub.add(item10 = new MenuItem("First")); sub.add(item11 = new MenuItem("Second")); sub.add(item12 = new MenuItem("Third")); edit.add(sub);

// these are checkable menu items MCA-III

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JAVA debug = new CheckboxMenuItem("Debug"); edit.add(debug); test = new CheckboxMenuItem("Testing"); edit.add(test);

mbar.add(edit);

// create an object to handle action and item events MyMenuHandler handler = new MyMenuHandler(this); // it to receive those events item1.addActionListener(handler); item2.addActionListener(handler); item3.addActionListener(handler); item4.addActionListener(handler); item5.addActionListener(handler); item6.addActionListener(handler); item7.addActionListener(handler); item8.addActionListener(handler); item9.addActionListener(handler); item10.addActionListener(handler); item11.addActionListener(handler); item12.addActionListener(handler); MCA-III

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JAVA debug.addItemListener(handler); test.addItemListener(handler);

// create an object to handle window events MyWindowAdapter adapter = new MyWindowAdapter(this); // it to receive those events addWindowListener(adapter); }

public void paint(Graphics g) { g.drawString(msg, 10, 200);

if(debug.getState()) g.drawString("Debug is on.", 10, 220); else g.drawString("Debug is off.", 10, 220);

if(test.getState()) g.drawString("Testing is on.", 10, 240); else g.drawString("Testing is off.", 10, 240); } MCA-III

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JAVA }

class MyWindowAdapter extends WindowAdapter { MenuFrame menuFrame; public MyWindowAdapter(MenuFrame menuFrame) { this.menuFrame = menuFrame; } public void windowClosing(WindowEvent we) { menuFrame.setVisible(false); } }

class MyMenuHandler implements ActionListener, ItemListener { MenuFrame menuFrame; public MyMenuHandler(MenuFrame menuFrame) { this.menuFrame = menuFrame; } // Handle action events public void actionPerformed(ActionEvent ae) { String msg = "You selected "; String arg = (String)ae.getActionCommand(); if(arg.equals("New...")) MCA-III

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JAVA msg += "New."; else if(arg.equals("Open...")) msg += "Open."; else if(arg.equals("Close")) msg += "Close."; else if(arg.equals("Quit...")) msg += "Quit."; else if(arg.equals("Edit")) msg += "Edit."; else if(arg.equals("Cut")) msg += "Cut."; else if(arg.equals("Copy")) msg += "Copy."; else if(arg.equals("Paste")) msg += "Paste."; else if(arg.equals("First")) msg += "First."; else if(arg.equals("Second")) msg += "Second."; else if(arg.equals("Third")) msg += "Third."; else if(arg.equals("Debug")) MCA-III

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JAVA msg += "Debug."; else if(arg.equals("Testing")) msg += "Testing."; menuFrame.msg = msg; menuFrame.repaint(); } // Handle item events public void itemStateChanged(ItemEvent ie) { menuFrame.repaint(); } } /* // Create frame window. public class MenuDemo extends Applet { Frame f;


setSize(new Dimension(width, height)); MCA-III

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JAVA

f.setSize(width, height); f.setVisible(true); }


public void stop() { f.setVisible(false); } } */ 13. // Demonstrate Dialog box. import java.awt.*; import java.awt.event.*; import java.applet.*; /* */ MCA-III

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JAVA

// Create a subclass of Dialog. class SampleDialog extends Dialog implements ActionListener { SampleDialog(Frame parent, String title) { super(parent, title, false); setLayout(new FlowLayout()); setSize(300, 200);

add(new Label("Press this button:")); Button b; add(b = new Button("Cancel")); b.addActionListener(this); }

public void actionPerformed(ActionEvent ae) { dispose(); }

public void paint(Graphics g) { g.drawString("This is in the dialog box", 10, 70); } } MCA-III

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JAVA

// Create a subclass of Frame. class MenuFrame extends Frame { String msg = ""; CheckboxMenuItem debug, test;



// create the menu items Menu file = new Menu("File"); MenuItem item1, item2, item3, item4; file.add(item1 = new MenuItem("New...")); file.add(item2 = new MenuItem("Open...")); file.add(item3 = new MenuItem("Close")); file.add(new MenuItem("-")); file.add(item4 = new MenuItem("Quit...")); mbar.add(file); MCA-III

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JAVA

Menu edit = new Menu("Edit"); MenuItem item5, item6, item7; edit.add(item5 = new MenuItem("Cut")); edit.add(item6 = new MenuItem("Copy")); edit.add(item7 = new MenuItem("Paste")); edit.add(new MenuItem("-"));

Menu sub = new Menu("Special", true); MenuItem item8, item9, item10; sub.add(item8 = new MenuItem("First")); sub.add(item9 = new MenuItem("Second")); sub.add(item10 = new MenuItem("Third")); edit.add(sub);

// these are checkable menu items debug = new CheckboxMenuItem("Debug"); edit.add(debug); test = new CheckboxMenuItem("Testing"); edit.add(test);

mbar.add(edit); MCA-III

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JAVA

// create an object to handle action and item events MyMenuHandler handler = new MyMenuHandler(this);

// it to receive those events item1.addActionListener(handler); item2.addActionListener(handler); item3.addActionListener(handler); item4.addActionListener(handler); item5.addActionListener(handler); item6.addActionListener(handler); item7.addActionListener(handler); item8.addActionListener(handler); item9.addActionListener(handler); item10.addActionListener(handler); debug.addItemListener(handler); test.addItemListener(handler);

// create an object to handle window events MyWindowAdapter adapter = new MyWindowAdapter(this); // it to receive those events addWindowListener(adapter); MCA-III

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JAVA } public void paint(Graphics g) { g.drawString(msg, 10, 200);


if(test.getState()) g.drawString("Testing is on.", 10, 240); else g.drawString("Testing is off.", 10, 240); } }

class MyWindowAdapter extends WindowAdapter { MenuFrame menuFrame; public MyWindowAdapter(MenuFrame menuFrame) { this.menuFrame = menuFrame; } public void windowClosing(WindowEvent we) { MCA-III

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JAVA menuFrame.dispose(); } }

class MyMenuHandler implements ActionListener, ItemListener { MenuFrame menuFrame; public MyMenuHandler(MenuFrame menuFrame) { this.menuFrame = menuFrame; } // Handle action events public void actionPerformed(ActionEvent ae) { String msg = "You selected "; String arg = (String)ae.getActionCommand(); // Activate a dialog box when New is selected. if(arg.equals("New...")) { msg += "New."; SampleDialog d = new SampleDialog(menuFrame, "New Dialog Box"); d.setVisible(true); } // Try defining other dialog boxes for these options. else if(arg.equals("Open...")) MCA-III

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JAVA msg += "Open."; else if(arg.equals("Close")) msg += "Close."; else if(arg.equals("Quit...")) msg += "Quit."; else if(arg.equals("Edit")) msg += "Edit."; else if(arg.equals("Cut")) msg += "Cut."; else if(arg.equals("Copy")) msg += "Copy."; else if(arg.equals("Paste")) msg += "Paste."; else if(arg.equals("First")) msg += "First."; else if(arg.equals("Second")) msg += "Second."; else if(arg.equals("Third")) msg += "Third."; else if(arg.equals("Debug")) msg += "Debug."; else if(arg.equals("Testing")) MCA-III

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JAVA msg += "Testing."; menuFrame.msg = msg; menuFrame.repaint(); } public void itemStateChanged(ItemEvent ie) { menuFrame.repaint(); } }

/* // Create frame window. public class DialogDemo extends Applet { Frame f;


setSize(width, height);

f.setSize(width, height); MCA-III

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JAVA f.setVisible(true); }


public void stop() { f.setVisible(false); } } */ 14. /* Demonstrate File Dialog box.

This is an application, not an applet. */ import java.awt.*; import java.awt.event.*;

// Create a subclass of Frame class SampleFrame extends Frame { SampleFrame(String title) { MCA-III

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JAVA super(title); // create an object to handle window events MyWindowAdapter adapter = new MyWindowAdapter(this); // it to receive those events addWindowListener(adapter); } }

class MyWindowAdapter extends WindowAdapter { SampleFrame sampleFrame; public MyWindowAdapter(SampleFrame sampleFrame) { this.sampleFrame = sampleFrame; } public void windowClosing(WindowEvent we) { sampleFrame.setVisible(false); } }

// Create frame window. class FileDialogDemo { public static void main(String args[]) { Frame f = new SampleFrame("File Dialog Demo"); MCA-III

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JAVA f.setVisible(true); f.setSize(100, 100);

FileDialog fd = new FileDialog(f, "File Dialog"); fd.setVisible(true); } } 15. // Demonstrate scroll bars. import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

public class SBDemo extends Applet implements AdjustmentListener, MouseMotionListener { String msg = ""; Scrollbar vertSB, horzSB;

public void init() { MCA-III

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JAVA int width = Integer.parseInt(getParameter("width")); int height = Integer.parseInt(getParameter("height"));

vertSB = new Scrollbar(Scrollbar.VERTICAL, 0, 1, 0, height); horzSB = new Scrollbar(Scrollbar.HORIZONTAL, 0, 1, 0, width);

add(vertSB); add(horzSB);

// to receive adjustment events vertSB.addAdjustmentListener(this); horzSB.addAdjustmentListener(this);

addMouseMotionListener(this); }

public void adjustmentValueChanged(AdjustmentEvent ae) { repaint(); }

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JAVA // Update scroll bars to reflect mouse dragging. public void mouseDragged(MouseEvent me) { int x = me.getX(); int y = me.getY(); vertSB.setValue(y); horzSB.setValue(x); repaint(); }

// Necessary for MouseMotionListener public void mouseMoved(MouseEvent me) { }

// Display current value of scroll bars. public void paint(Graphics g) { msg = "Vertical: " + vertSB.getValue(); msg += ", Horizontal: " + horzSB.getValue(); g.drawString(msg, 6, 160);

// show current mouse drag position g.drawString("*", horzSB.getValue(), vertSB.getValue()); MCA-III

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JAVA } } 16. // Demonstrate TextArea. import java.awt.*; import java.applet.*; /* */

public class TextAreaDemo extends Applet { public void init() { String val = "There are two ways of constructing " + "a software design.\n" + "One way is to make it so simple\n" + "that there are obviously no deficiencies.\n" + "And the other way is to make it so complicated\n" + "that there are no obvious deficiencies.\n\n" + "

-C.A.R. Hoare\n\n" +

"There's an old story about the person who wished\n" + "his computer were as easy to use as his telephone.\n" + "That wish has come true,\n" + MCA-III

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JAVA "since I no longer know how to use my telephone.\n\n" + "

-Bjarne Stroustrup, AT&T, (inventor of C++)";

TextArea text = new TextArea(val, 10, 30); add(text); } } 17. // Demonstrate text field. import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

public class TextFieldDemo extends Applet implements ActionListener {

TextField name, ;

public void init() { MCA-III

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JAVA Label namep = new Label("Name: ", Label.RIGHT); Label p = new Label(": ", Label.RIGHT); name = new TextField(12); = new TextField(8); .setEchoChar('?');

add(namep); add(name); add(p); add();

// to receive action events name.addActionListener(this); .addActionListener(this); }

// pressed Enter. public void actionPerformed(ActionEvent ae) { repaint(); }

public void paint(Graphics g) { MCA-III

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JAVA g.drawString("Name: " + name.getText(), 6, 60); g.drawString("Selected text in name: " + name.getSelectedText(), 6, 80); g.drawString(": " + .getText(), 6, 100); } } 18. // Demonstrate text field. import java.awt.*; import java.awt.event.*; import java.applet.*; /* */

class SampleFrame extends Frame { SampleFrame(String title) { super(title); // create an object to handle window events MyWindowAdapter adapter = new MyWindowAdapter(this); // it to receive those events addWindowListener(adapter); MCA-III

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JAVA } }

class MyWindowAdapter extends WindowAdapter { SampleFrame sampleFrame; public MyWindowAdapter(SampleFrame sampleFrame) { this.sampleFrame = sampleFrame; } public void windowClosing(WindowEvent we) { sampleFrame.setVisible(false); } }

public class TextFieldDemo1 extends Applet implements ActionListener {

TextField name, ; Button b1; String s1; Frame f; public void init() { MCA-III

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JAVA Label namep = new Label("Name: ", Label.RIGHT); Label p = new Label(": ", Label.RIGHT); name = new TextField(12); = new TextField(8); .setEchoChar('?'); b1=new Button("ok");

add(namep); add(name); add(p); add(); add(b1);

// to receive action events name.addActionListener(this); .addActionListener(this); b1.addActionListener(this); }

// pressed Enter. public void actionPerformed(ActionEvent ae) { MCA-III

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JAVA repaint(); String s=ae.getActionCommand(); if(s.equals("ok")) f=new SampleFrame("button press"); f.setSize(200,200); f.setVisible(true);

}

public void paint(Graphics g) { g.drawString("Name: " + name.getText(), 6, 60); g.drawString("Selected text in name: " + name.getSelectedText(), 6, 80); g.drawString(": " + .getText(), 6, 100);

} } 19. import java.awt.*; import java.awt.event.*; import java.applet.*;

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JAVA

// Create a subclass of Dialog. class SampleDialog1 extends Dialog implements ActionListener { SampleDialog1(Frame parent, String title) { super(parent, title, false); setLayout(new FlowLayout()); setSize(300, 200);

add(new Label("Press this button:")); Button b; add(b = new Button("Cancel")); b.addActionListener(this); }

public void actionPerformed(ActionEvent ae) { dispose(); }

public void paint(Graphics g) { g.drawString("This is in the dialog box", 10, 70); } } MCA-III

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JAVA

class MenuFrame extends Frame { String msg = "";

CheckboxMenuItem debug, test;



// create the menu items Menu file = new Menu("File"); MenuItem item1, item2, item3, item4; file.add(item1 = new MenuItem("New...")); file.add(item2 = new MenuItem("Open...")); file.add(item3 = new MenuItem("Close")); file.add(new MenuItem("-")); file.add(item4 = new MenuItem("Quit...")); mbar.add(file); MCA-III

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JAVA

// these are checkable menu items debug = new CheckboxMenuItem("Debug"); file.add(debug); test = new CheckboxMenuItem("Testing"); file.add(test);

// create an object to handle action and item events MyMenuHandler handler = new MyMenuHandler(this);

// it to receive those events item1.addActionListener(handler); item2.addActionListener(handler); item3.addActionListener(handler); item4.addActionListener(handler);

debug.addItemListener(handler); test.addItemListener(handler);

// create an object to handle window events MCA-III

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JAVA MyWindowAdapter adapter = new MyWindowAdapter(this); // it to receive those events addWindowListener(adapter); } public void paint(Graphics g) { g.drawString(msg, 10, 200);


if(test.getState()) g.drawString("Testing is on.", 10, 240); else g.drawString("Testing is off.", 10, 240); } }

class MyWindowAdapter extends WindowAdapter { MenuFrame menuFrame; public MyWindowAdapter(MenuFrame menuFrame) { MCA-III

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JAVA this.menuFrame = menuFrame; } public void windowClosing(WindowEvent we) { menuFrame.dispose(); } }

class MyMenuHandler implements ActionListener, ItemListener { MenuFrame menuFrame; public MyMenuHandler(MenuFrame menuFrame) { this.menuFrame = menuFrame; } // Handle action events public void actionPerformed(ActionEvent ae) { String msg = "You selected ";

String arg = (String)ae.getActionCommand(); // Activate a dialog box when New is selected. if(arg.equals("New...")) { msg += "New.";

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JAVA SampleDialog1 d = new SampleDialog1(menuFrame, "New Dialog Box"); d.setVisible(true); System.out.println("Hello World!"); } // Try defining other dialog boxes for these options. else if(arg.equals("Open...")){ msg += "Open."; FileDialog d = new FileDialog(menuFrame, "open Dialog Box",FileDialog.LOAD); d.setVisible(true); }

else if(arg.equals("Quit")) msg += "Quite."; else if(arg.equals("Close")) msg += "Close.";

else if(arg.equals("Debug")) msg += "Debug."; else if(arg.equals("Testing")) msg += "Testing."; MCA-III

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JAVA menuFrame.msg = msg; menuFrame.repaint(); } public void itemStateChanged(ItemEvent ie) { menuFrame.repaint(); } } class f1 { public static void main(String[] args) { Frame f;

f = new MenuFrame("Menu Demo");

f.setSize(300, 300); f.setVisible(true); } }

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JAVA

SWINGS PROGRAMS 1. import java.awt.*; import java.awt.event.*; import javax.swing.*; /* */

public class JButtonDemo extends JApplet implements ActionListener { JTextField jtf;


// Get content pane Container contentPane = getContentPane(); contentPane.setLayout(new FlowLayout());

// Add buttons to content pane MCA-III

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JAVA ImageIcon = new ImageIcon(".gif"); JButton jb = new JButton(); jb.setActionCommand(""); jb.addActionListener(this); contentPane.add(jb);

ImageIcon = new ImageIcon(".gif"); jb = new JButton(); jb.setActionCommand(""); jb.addActionListener(this); contentPane.add(jb);

ImageIcon italy = new ImageIcon("italy.gif"); jb = new JButton(italy); jb.setActionCommand("Italy"); jb.addActionListener(this); contentPane.add(jb);

ImageIcon japan = new ImageIcon("japan.gif"); jb = new JButton(japan); jb.setActionCommand("Japan"); jb.addActionListener(this); MCA-III

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JAVA contentPane.add(jb);

// Add text field to content pane jtf = new JTextField(15); contentPane.add(jtf); }

public void actionPerformed(ActionEvent ae) { jtf.setText(ae.getActionCommand()); } } 2. import java.awt.*; import java.awt.event.*; import javax.swing.*; /* */

public class JCheckBoxDemo extends JApplet implements ItemListener { JTextField jtf; MCA-III

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JAVA



// Create icons ImageIcon normal = new ImageIcon("normal.gif"); ImageIcon rollover = new ImageIcon("rollover.gif"); ImageIcon selected = new ImageIcon("selected.gif");

// Add check boxes to the content pane JCheckBox cb = new JCheckBox("C", normal); cb.setRolloverIcon(rollover); cb.setSelectedIcon(selected); cb.addItemListener(this); contentPane.add(cb);

cb = new JCheckBox("C++", normal); cb.setRolloverIcon(rollover); cb.setSelectedIcon(selected); MCA-III

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JAVA cb.addItemListener(this); contentPane.add(cb);

cb = new JCheckBox("Java", normal); cb.setRolloverIcon(rollover); cb.setSelectedIcon(selected); cb.addItemListener(this); contentPane.add(cb);

cb = new JCheckBox("Perl", normal); cb.setRolloverIcon(rollover); cb.setSelectedIcon(selected); cb.addItemListener(this); contentPane.add(cb);

// Add text field to the content pane jtf = new JTextField(15); contentPane.add(jtf); }

public void itemStateChanged(ItemEvent ie) { JCheckBox cb = (JCheckBox)ie.getItem(); MCA-III

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JAVA jtf.setText(cb.getText()); } } 3. import java.awt.*; import java.awt.event.*; import javax.swing.*; /* */

public class JComboBoxDemo extends JApplet implements ItemListener { JLabel jl; ImageIcon , , italy, japan;



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JAVA // Create a combo box and add it // to the JComboBox jc = new JComboBox(); jc.addItem(""); jc.addItem(""); jc.addItem("Italy"); jc.addItem("Japan"); jc.addItemListener(this); contentPane.add(jc);

// Create label jl = new JLabel(new ImageIcon(".gif")); contentPane.add(jl); }

public void itemStateChanged(ItemEvent ie) { String s = (String)ie.getItem(); jl.setIcon(new ImageIcon(s + ".gif")); } } 4. import java.awt.*; import javax.swing.*; MCA-III

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JAVA /* */

public class JLabelDemo extends JApplet {

public void init() { // Get content pane Container contentPane = getContentPane();

// Create an icon ImageIcon ii = new ImageIcon(".gif");

// Create a label JLabel jl = new JLabel("", ii, JLabel.CENTER);

// Add label to the content pane contentPane.add(jl); } } 5. import java.awt.*; MCA-III

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JAVA import java.awt.event.*; import javax.swing.*; /* */

public class JRadioButtonDemo extends JApplet implements ActionListener { JTextField tf;



// Add radio buttons to content pane JRadioButton b1 = new JRadioButton("A"); b1.addActionListener(this); contentPane.add(b1);

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JAVA JRadioButton b2 = new JRadioButton("B"); b2.addActionListener(this); contentPane.add(b2);

JRadioButton b3 = new JRadioButton("C"); b3.addActionListener(this); contentPane.add(b3);

// Define a button group ButtonGroup bg = new ButtonGroup(); bg.add(b1); bg.add(b2); bg.add(b3);

// Create a text field and add it // to the content pane tf = new JTextField(5); contentPane.add(tf); }

public void actionPerformed(ActionEvent ae) { tf.setText(ae.getActionCommand()); MCA-III

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JAVA } } 6. import java.awt.*; import javax.swing.*; /* */

public class JScrollPaneDemo extends JApplet {


// Get content pane Container contentPane = getContentPane(); contentPane.setLayout(new BorderLayout());

// Add 400 buttons to a J jp = new J(); jp.setLayout(new GridLayout(20, 20)); int b = 0; for(int i = 0; i < 20; i++) { MCA-III

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JAVA for(int j = 0; j < 20; j++) { jp.add(new JButton("Button " + b)); ++b; } }

// Add to a scroll pane int v = ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED; int h = ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED; JScrollPane jsp = new JScrollPane(jp, v, h);

// Add scroll pane to the content pane contentPane.add(jsp, BorderLayout.CENTER); } } 7. import javax.swing.*; /* */

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JAVA

public class JTabbedPaneDemo extends JApplet {


JTabbedPane jtp = new JTabbedPane(); jtp.addTab("Cities", new Cities()); jtp.addTab("Colors", new Colors()); jtp.addTab("Flavors", new Flavors()); getContentPane().add(jtp); } }

class Cities extends J {

public Cities() {

JButton b1 = new JButton("New York"); add(b1); JButton b2 = new JButton("London"); add(b2); JButton b3 = new JButton("Hong Kong"); MCA-III

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JAVA add(b3); JButton b4 = new JButton("Tokyo"); add(b4); } }

class Colors extends J {

public Colors() {

JCheckBox cb1 = new JCheckBox("Red"); add(cb1); JCheckBox cb2 = new JCheckBox("Green"); add(cb2); JCheckBox cb3 = new JCheckBox("Blue"); add(cb3); } }

class Flavors extends J {

public Flavors() { MCA-III

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JAVA

JComboBox jcb = new JComboBox(); jcb.addItem("Vanilla"); jcb.addItem("Chocolate"); jcb.addItem("Strawberry"); add(jcb); } }

8. import java.awt.*; import javax.swing.*; /* */

public class JTableDemo extends JApplet {


// Get content pane MCA-III

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JAVA Container contentPane = getContentPane();

// Set layout manager contentPane.setLayout(new BorderLayout());

// Initialize column headings final String[] colHeads = { "Name", "Phone", "Fax" };

// Initialize data final Object[][] data = { { "Gail", "4567", "8675" }, { "Ken", "7566", "5555" }, { "Viviane", "5634", "5887" }, { "Melanie", "7345", "9222" }, { "Anne", "1237", "3333" }, { "John", "5656", "3144" }, { "Matt", "5672", "2176" }, { "Claire", "6741", "4244" }, { "Erwin", "9023", "5159" }, { "Ellen", "1134", "5332" }, { "Jennifer", "5689", "1212" }, { "Ed", "9030", "1313" }, MCA-III

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JAVA { "Helen", "6751", "1415" } };

// Create the table JTable table = new JTable(data, colHeads);

// Add tree to a scroll pane int v = ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED; int h = ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED; JScrollPane jsp = new JScrollPane(table, v, h);

// Add scroll pane to the content pane contentPane.add(jsp, BorderLayout.CENTER); } } 9. import java.awt.*; import javax.swing.*; /* */ MCA-III

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JAVA

public class JTextFieldDemo extends JApplet { JTextField jtf;



// Add text field to content pane jtf = new JTextField(15); contentPane.add(jtf); } } 10. import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.swing.tree.*; /* MCA-III

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JAVA */

public class JTreeEvents extends JApplet { JTree tree; JTextField jtf;


// Get content pane Container contentPane = getContentPane();


// Create top node of tree DefaultMutableTreeNode top = new DefaultMutableTreeNode("Options");

// Create subtree of "A" DefaultMutableTreeNode a = new DefaultMutableTreeNode("A"); top.add(a); MCA-III

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JAVA DefaultMutableTreeNode a1 = new DefaultMutableTreeNode("A1"); a.add(a1); DefaultMutableTreeNode a2 = new DefaultMutableTreeNode("A2"); a.add(a2);

// Create subtree of "B" DefaultMutableTreeNode b = new DefaultMutableTreeNode("B"); top.add(b); DefaultMutableTreeNode b1 = new DefaultMutableTreeNode("B1"); b.add(b1); DefaultMutableTreeNode b2 = new DefaultMutableTreeNode("B2"); b.add(b2); DefaultMutableTreeNode b3 = new DefaultMutableTreeNode("B3"); b.add(b3);

// Create tree tree = new JTree(top);

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JAVA // Add tree to a scroll pane int v = ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED; int h = ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED; JScrollPane jsp = new JScrollPane(tree, v, h);

// Add scroll pane to the content pane contentPane.add(jsp, BorderLayout.CENTER);

// Add text field to applet jtf = new JTextField("", 20); contentPane.add(jtf, BorderLayout.SOUTH);

// Anonymous inner class to handle mouse clicks tree.addMouseListener(new MouseAdapter() { public void mouseClicked(MouseEvent me) { doMouseClicked(me); } }); }

void doMouseClicked(MouseEvent me) { MCA-III

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JAVA TreePath tp = tree.getPathForLocation(me.getX(), me.getY()); if(tp != null) jtf.setText(tp.toString()); else jtf.setText(""); } }

11. import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.swing.tree.*; /* */

public class JTreeEvents1 extends JApplet { JTree tree; JTextField jtf;

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JAVA public void init() {

// Get content pane Container contentPane = getContentPane();


// Create top node of tree DefaultMutableTreeNode top = new DefaultMutableTreeNode("Options");

// Create subtree of "A" DefaultMutableTreeNode a = new DefaultMutableTreeNode("A"); top.add(a); DefaultMutableTreeNode a1 = new DefaultMutableTreeNode("A1"); a.add(a1); DefaultMutableTreeNode a2 = new DefaultMutableTreeNode("A2"); a.add(a2);

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JAVA // Create subtree of "B" DefaultMutableTreeNode b = new DefaultMutableTreeNode("B"); top.add(b); DefaultMutableTreeNode b1 = new DefaultMutableTreeNode("B1"); b.add(b1); DefaultMutableTreeNode b2 = new DefaultMutableTreeNode("B2"); b.add(b2); DefaultMutableTreeNode b3 = new DefaultMutableTreeNode("B3"); b.add(b3);

// Create tree tree = new JTree(top);

// Add tree to a scroll pane int v = ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED; int h = ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED; JScrollPane jsp = new JScrollPane(tree, v, h);

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JAVA // Add scroll pane to the content pane contentPane.add(jsp, BorderLayout.CENTER);

// Add text field to applet jtf = new JTextField("", 20); contentPane.add(jtf, BorderLayout.SOUTH);

// Anonymous inner class to handle mouse clicks tree.addMouseListener(new MouseAdapter() { public void mouseClicked(MouseEvent me) { doMouseClicked(me); } }); }

void doMouseClicked(MouseEvent me) { TreePath tp = tree.getPathForLocation(me.getX(), me.getY()); if(tp != null) jtf.setText(tp.toString()); else jtf.setText(""); } MCA-III

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JAVA }

NETWORKING PROGRAMS 1. //Demonstrate Sockets. import java.net.*; import java.io.*;

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

Socket s = new Socket("localhost", 777); InputStream in = s.getInputStream(); BufferedReader br=new BufferedReader(new InputStreamReader(in)); OutputStream out = s.getOutputStream(); String str;

while ((str=br.readLine()) != null) { System.out.print("fro ser"+str); } br.close();

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JAVA s.close(); } } 2. // Demonstrate InetAddress. import java.net.*;

class InetAddressTest { public static void main(String args[]) throws UnknownHostException { InetAddress Address = InetAddress.getLocalHost(); System.out.println(Address); Address = InetAddress.getByName("starwave.com"); System.out.println(Address); InetAddress SW[] = InetAddress.getAllByName("www.nba.com"); for (int i=0; i<SW.length; i++) System.out.println(SW[i]); } } 3. // Demonstrate URL. import java.net.*; class patrickURL { MCA-III

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JAVA public static void main(String args[]) throws MalformedURLException { URL hp = new URL("http://www.starwave.com/people/naughton/");

System.out.println("Protocol: " + hp.getProtocol()); System.out.println("Port: " + hp.getPort()); System.out.println("Host: " + hp.getHost()); System.out.println("File: " + hp.getFile()); System.out.println("Ext:" + hp.toExternalForm()); } } 4. //Demonstrate Sockets. import java.net.*; import java.io.*;

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

ServerSocket ss = new ServerSocket(777); Socket s=ss.accept(); System.out.print("connection established");

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JAVA OutputStream out = s.getOutputStream(); PrintStream ps=new PrintStream(out); String str = "hello client" ; ps.println(str); ps.println("bye"); ps.close(); s.close(); } } 5. // Demonstrate URLConnection. import java.net.*; import java.io.*; import java.util.Date;

class UCDemo { public static void main(String args[]) throws Exception { int c; URL hp = new URL("http://www.starwave.com/people/naughton/"); URLConnection hpCon = hp.openConnection();

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JAVA System.out.println("Date: " + new Date(hpCon.getDate())); System.out.println("Content-Type: " + hpCon.getContentType()); System.out.println("Expires: " + hpCon.getExpiration()); System.out.println("Last-Modified: " + new Date(hpCon.getLastModified())); int len = hpCon.getContentLength(); System.out.println("Content-Length: " + len); if (len > 0) { System.out.println("=== Content ==="); InputStream input = hpCon.getInputStream(); int i = len; while (((c = input.read()) != -1) && (--i > 0)) { System.out.print((char) c); } input.close(); } else { System.out.println("No Content Available"); } } } 6. //Demonstrate Sockets.

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

class Whois { public static void main(String args[]) throws Exception { int c; Socket s = new Socket("internic.net", 43); InputStream in = s.getInputStream(); OutputStream out = s.getOutputStream(); String str = (args.length == 0 ? "starwave-dom" : args[0]) + "\n"; byte buf[] = str.getBytes(); out.write(buf); while ((c = in.read()) != -1) { System.out.print((char) c); } s.close(); } } 7. // Demonstrate Datagrams. import java.net.*;

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JAVA class WriteServer { public static int serverPort = 666; public static int clientPort = 999; public static int buffer_size = 1024; public static DatagramSocket ds; public static byte buffer[] = new byte[buffer_size];

public static void TheServer() throws Exception { int pos=0; while (true) { int c = System.in.read(); switch (c) { case -1: System.out.println("Server Quits."); return; case '\r': break; case '\n': ds.send(new DatagramPacket(buffer,pos, InetAddress.getLocalHost(),clientPort)); pos=0; break; MCA-III

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JAVA default: buffer[pos++] = (byte) c; } } }

public static void TheClient() throws Exception { while(true) { DatagramPacket p = new DatagramPacket(buffer, buffer.length); ds.receive(p); System.out.println(new String(p.getData(), 0, p.getLength())); } }

public static void main(String args[]) throws Exception { if(args.length == 1) { ds = new DatagramSocket(serverPort); TheServer(); } else { ds = new DatagramSocket(clientPort); TheClient(); MCA-III

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JAVA } } }

MCA-III

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