Java program to find sum of numbers present in a string..

Numbers are apart from from characters by spaces ...like "12 gaurav 3"

Here is the code ....

       
import java.io.*;
public class BetterProgrammerTask {

 public static int getSumOfNumbers(String s) {
  int sum = 0;
  String[] bw = s.split(" ");
  for (int k = 0; k < bw.length; k++) {
   if (isNumeric(bw[k]) == true)
    sum = sum + Integer.parseInt(bw[k]);
  }
  return sum;
 }

 public static boolean isNumeric(String kts) {
  try {
   double d = Double.parseDouble(kts);
  } catch (NumberFormatException nfe) {
   return false;
  }
  return true;
 }

 public static void main(String args[]) throws Exception {
  BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  String str = br.readLine();
  getSumOfNumbers(str);
  System.out.println(getSumOfNumbers(str));
 }
}

       
 

Java program to find the greater of two numbers without using any relational operator ...

Here is the code .....

       
import java.io.*;
import java.util.*;

public class Greater {

 int great(int a, int b) {
  int c = a - b;
  int k = (c >> 31) & 0x1;
  System.out.println(k);
  //int g=a-k(a-b);
  return a - k * (a - b);
 }
 public static void main(String args[]) {
  int a = 6, b = 3;
  Greater d = new Greater();
  System.out.println("the greater no. is " + d.great(a, b));
 }
}

       
 

Java program to find sum of two numbers without using '+' operator ..

Here is the code ....

       
public class Sumfrom {

 int Sumis(int a, int b) {
  if (b == 0) return a;
  int sum = (a ^ b);
  int carry = (a & b) << 1;
  return Sumis(sum, carry);
 }

 public static void main(String args[]) {
  int a = 34, b = 2;
  Sumfrom d = new Sumfrom();
  System.out.println("the sum is " + d.Sumis(a, b));
 }

}

       
 

Java program to remove duplicates from a character array .

Here is the code ....

       

public class P13 {
 public static void main(String args[]) {
  char[] chr = {
   'g',
   'a',
   'g',
   'r',
   'p',
   'k',
   't',
   'k',
   'r',
   's'
  };
  boolean[] boo = new boolean[256];
  int cal = 0;
  for (int i = 0, val; i < chr.length; i++) {

   if (i < chr.length - cal) {

    val = chr[i];
    if (boo[val]) {
     cal = cal + 1;

     for (int k = i; k < chr.length - 1; k++) {
      chr[k] = chr[k + 1];
     }
     chr[chr.length - 1] = '\0';
     i = i - 1;
    } else boo[val] = true;
    //System.out.println("hello2");

   } else {
    break;
   }
  }

  for (int h = 0; h < chr.length; h++)
   System.out.print(chr[h]);

 }
}

       
 

java program to copy values from a arraylist to array.

Here is the source code ...

       

import java.util.*;
class Arraylist_to_array {
 public static void main(String[] a) {
  ArrayList k = new ArrayList();
  k.add(new Integer(1));
  k.add(new Integer(2));
  k.add(new Integer(3));
  k.add(new Integer(4));
  k.add(new Integer(5));
  k.add(new Integer(4));
  System.out.println("contents of ArrayList=" + k);

  Object arr[] = new Object[6];
  arr = k.toArray();
  int sum = 0, i;
  for (i = 0; i < arr.length; i++) {
   sum += ((Integer) arr[i]).intValue();
  }
  System.out.println("sum of the contents of the array=" + sum);
 }
}

       
 

A program to check whether a string is a substring of a given another string or not .

Here is the source code .....

       

import java.io.*;
public class P18 {
 public static void main(String args[]) {
  String s1 = "ur";
  String s2 = "gaurav";
  P18 ab = new P18();
  ab.isString(s1, s2);
 }

 void isString(String s1, String s2) {
  int k;

  if (s1.length() > s2.length()) {
   System.out.println("string is not substring");
   return;
  }

  for (int i = 0, s = 0; i < s2.length() - s1.length(); i++) {
   if (s2.charAt(i) == s1.charAt(s)) {
    for (k = i; k < i + s1.length(); k++) {
     if (s1.charAt(s) == s2.charAt(k)) {
      s++;
     } else {
      s = 0;
      break;
     }
    }
    if (k == i + s1.length()) {
     System.out.println("string is substring");
     return;
    }
   }

  }
  System.out.println("string is not the substring");
 }
}

       
 

Source code for Calculator application implemented using java swing API

Source code for Calculator application implemented using java swing API ......

here is the code for the application ....its a mini project although a desktop application and it works well because i thoroughly tested it ...

       

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.KeyStroke;

public class Calculator extends JFrame implements ActionListener {
 final int MAX_INPUT_LENGTH = 15;
 final int INPUT_MODE = 0;
 final int RESULT_MODE = 1;
 final int ERROR_MODE = 2;
 int displayMode;

 boolean clearOnNextDigit, percent;
 double lastNumber;
 String lastOperator;

 private JMenu jmenuFile, jmenuHelp;
 private JMenuItem jmenuitemExit, jmenuitemAbout;

 private JLabel jlbOutput;
 private JButton jbnButtons[];
 private JPanel jplMaster, jplBackSpace, jplControl;

 Font f1 = new Font("Times New Roman", 0, 18);
 Font f12 = new Font("Times New Roman", 1, 18);

 public Calculator() {
  jmenuFile = new JMenu("File");
  jmenuFile.setFont(f12);
  jmenuFile.setMnemonic(KeyEvent.VK_F);

  jmenuitemExit = new JMenuItem("Exit");
  jmenuitemExit.setFont(f1);
  jmenuitemExit.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_X,
   ActionEvent.CTRL_MASK));
  jmenuFile.add(jmenuitemExit);

  jmenuHelp = new JMenu("Help");
  jmenuHelp.setFont(f12);
  jmenuHelp.setMnemonic(KeyEvent.VK_H);

  jmenuitemAbout = new JMenuItem("About Calculator");
  jmenuitemAbout.setFont(f1);
  jmenuHelp.add(jmenuitemAbout);

  JMenuBar mb = new JMenuBar();
  mb.add(jmenuFile);
  mb.add(jmenuHelp);
  setJMenuBar(mb);

  setBackground(Color.gray);

  jplMaster = new JPanel();

  jlbOutput = new JLabel("0");
  jlbOutput.setHorizontalTextPosition(JLabel.RIGHT);
  jlbOutput.setBackground(Color.WHITE);
  jlbOutput.setOpaque(true);
  getContentPane().add(jlbOutput, BorderLayout.NORTH);

  jbnButtons = new JButton[18];
  JPanel jplButtons = new JPanel();
  for (int i = 0; i <= 9; i++) {
   jbnButtons[i] = new JButton(String.valueOf(i));
  }

  jbnButtons[10] = new JButton(".");
  jbnButtons[11] = new JButton("=");
  jbnButtons[12] = new JButton("/");
  jbnButtons[13] = new JButton("*");
  jbnButtons[14] = new JButton("-");
  jbnButtons[15] = new JButton("+");

  jplBackSpace = new JPanel();
  jplBackSpace.setLayout(new GridLayout(1, 1, 2, 3));

  jbnButtons[16] = new JButton("Backspace");
  jplBackSpace.add(jbnButtons[16]);
  jplControl = new JPanel();
  jplControl.setLayout(new GridLayout(1, 2, 2, 3));

  jbnButtons[17] = new JButton("C");
  jplControl.add(jbnButtons[17]);

  for (int i = 0; i < jbnButtons.length; i++) {
   jbnButtons[i].setFont(f12);

   if (i < 10)
    jbnButtons[i].setForeground(Color.blue);

   else
    jbnButtons[i].setForeground(Color.red);
  }

  jplButtons.setLayout(new GridLayout(4, 5, 2, 4));

  for (int i = 7; i <= 9; i++) {
   jplButtons.add(jbnButtons[i]);
  }

  jplButtons.add(jbnButtons[10]);
  jplButtons.add(jbnButtons[12]);


  for (int i = 4; i <= 6; i++) {
   jplButtons.add(jbnButtons[i]);
  }

  jplButtons.add(jbnButtons[14]);
  jplButtons.add(jbnButtons[11]);



  for (int i = 1; i <= 3; i++) {
   jplButtons.add(jbnButtons[i]);
  }

  jplButtons.add(jbnButtons[0]);
  jplButtons.add(jbnButtons[13]);
  jplButtons.add(jbnButtons[15]);
  jplButtons.add(jbnButtons[16]);
  jplButtons.add(jbnButtons[17]);


  jplMaster.setLayout(new BorderLayout());
  jplMaster.add(jplBackSpace, BorderLayout.WEST);
  jplMaster.add(jplControl, BorderLayout.EAST);
  jplMaster.add(jplButtons, BorderLayout.SOUTH);

  getContentPane().add(jplMaster, BorderLayout.SOUTH);
  requestFocus();

  for (int i = 0; i < jbnButtons.length; i++) {
   jbnButtons[i].addActionListener(this);
  }

  jmenuitemAbout.addActionListener(this);
  jmenuitemExit.addActionListener(this);

  clearAll();

  addWindowListener(new WindowAdapter() {

   public void windowClosed(WindowEvent e) {
    System.exit(0);
   }
  });
  this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 }


 public void actionPerformed(ActionEvent e) {
  double result = 0;

  if (e.getSource() == jmenuitemAbout) {
   JDialog dlgAbout = new CustomABOUTDialog(this, "About Java Swing Calculator", true);
   dlgAbout.setVisible(true);
  } else if (e.getSource() == jmenuitemExit) {
   System.exit(0);
  }
  for (int i = 0; i < jbnButtons.length; i++) {
   if (e.getSource() == jbnButtons[i]) {
    switch (i) {
     case 0:
      addDigitToDisplay(i);
      break;

     case 1:
      addDigitToDisplay(i);
      break;

     case 2:
      addDigitToDisplay(i);
      break;

     case 3:
      addDigitToDisplay(i);
      break;

     case 4:
      addDigitToDisplay(i);
      break;

     case 5:
      addDigitToDisplay(i);
      break;

     case 6:
      addDigitToDisplay(i);
      break;

     case 7:
      addDigitToDisplay(i);
      break;

     case 8:
      addDigitToDisplay(i);
      break;

     case 9:
      addDigitToDisplay(i);
      break;


     case 10: // decimal point
      addDecimalPoint();
      break;

     case 11: // =
      processEquals();
      break;

     case 12: // divide
      processOperator("/");
      break;

     case 13: // *
      processOperator("*");
      break;

     case 14: // -
      processOperator("-");
      break;

     case 15: // +
      processOperator("+");
      break;



     case 16: // backspace
      if (displayMode != ERROR_MODE) {
       setDisplayString(getDisplayString().substring(0,
        getDisplayString().length() - 1));

       if (getDisplayString().length() < 1)
        setDisplayString("0");
      }
      break;


     case 17: // C
      clearAll();
      break;
    }
   }
  }
 }

 void setDisplayString(String s) {
  jlbOutput.setText(s);
 }

 String getDisplayString() {
  return jlbOutput.getText();
 }

 void addDigitToDisplay(int digit) {
  if (clearOnNextDigit)
   setDisplayString("");

  String inputString = getDisplayString();

  if (inputString.indexOf("0") == 0) {
   inputString = inputString.substring(1);
  }

  if ((!inputString.equals("0") || digit > 0) && inputString.length() < MAX_INPUT_LENGTH) {
   setDisplayString(inputString + digit);
  }


  displayMode = INPUT_MODE;
  clearOnNextDigit = false;
 }

 void addDecimalPoint() {
  displayMode = INPUT_MODE;

  if (clearOnNextDigit)
   setDisplayString("");

  String inputString = getDisplayString();
  if (inputString.indexOf(".") < 0)
   setDisplayString(new String(inputString + "."));
 }



 void clearAll() {
  setDisplayString("0");
  lastOperator = "0";
  lastNumber = 0;
  displayMode = INPUT_MODE;
  clearOnNextDigit = true;
 }



 double getNumberInDisplay() {
  String input = jlbOutput.getText();
  return Double.parseDouble(input);
 }

 void processOperator(String op) {
  if (displayMode != ERROR_MODE) {
   double numberInDisplay = getNumberInDisplay();

   if (!lastOperator.equals("0")) {
    try {
     double result = processLastOperator();
     displayResult(result);
     lastNumber = result;
    } catch (DivideByZeroException e) {}
   } else {
    lastNumber = numberInDisplay;
   }

   clearOnNextDigit = true;
   lastOperator = op;
  }
 }

 void processEquals() {
  double result = 0;

  if (displayMode != ERROR_MODE) {
   try {
    result = processLastOperator();
    displayResult(result);
   } catch (DivideByZeroException e) {
    displayError("Cannot divide by zero!");
   }

   lastOperator = "0";
  }
 }

 double processLastOperator() throws DivideByZeroException {
  double result = 0;
  double numberInDisplay = getNumberInDisplay();

  if (lastOperator.equals("/")) {
   if (numberInDisplay == 0)
    throw (new DivideByZeroException());

   result = lastNumber / numberInDisplay;
  }

  if (lastOperator.equals("*"))
   result = lastNumber * numberInDisplay;

  if (lastOperator.equals("-"))
   result = lastNumber - numberInDisplay;

  if (lastOperator.equals("+"))
   result = lastNumber + numberInDisplay;

  return result;
 }

 void displayResult(double result) {
  setDisplayString(Double.toString(result));
  lastNumber = result;
  displayMode = RESULT_MODE;
  clearOnNextDigit = true;
 }

 void displayError(String errorMessage) {
  setDisplayString(errorMessage);
  lastNumber = 0;
  displayMode = ERROR_MODE;
  clearOnNextDigit = true;
 }

 public static void main(String args[]) {
  Calculator calci = new Calculator();
  Container contentPane = calci.getContentPane();
  calci.setTitle("Java Swing Calculator");
  calci.setSize(400, 360);
  calci.pack();
  calci.setLocation(300, 290);
  calci.setVisible(true);
  calci.setResizable(false);
 }

}
class DivideByZeroException extends Exception {
 public DivideByZeroException() {
  super();
 }

 public DivideByZeroException(String s) {
  super(s);
 }
}

class CustomABOUTDialog extends JDialog implements ActionListener {
 JButton jbnOk;

 CustomABOUTDialog(JFrame parent, String title, boolean modal) {
  super(parent, title, modal);
  setBackground(Color.black);

  JPanel p1 = new JPanel(new FlowLayout(FlowLayout.CENTER));

  StringBuffer text = new StringBuffer();
  text.append("Calculator Information\n\n");
  text.append("Developer: Amita Sikarwar\n class:  B.C.A 5th sem\n Roll No:  124\n\n");
  text.append("Version: 1.0");

  JTextArea jtAreaAbout = new JTextArea(5, 16);
  jtAreaAbout.setText(text.toString());
  jtAreaAbout.setFont(new Font("Times New Roman", 1, 13));
  jtAreaAbout.setEditable(false);

  p1.add(jtAreaAbout);
  p1.setBackground(Color.red);
  getContentPane().add(p1, BorderLayout.CENTER);

  JPanel p2 = new JPanel(new FlowLayout(FlowLayout.CENTER));
  jbnOk = new JButton(" OK ");
  jbnOk.addActionListener(this);

  p2.add(jbnOk);
  getContentPane().add(p2, BorderLayout.SOUTH);

  setLocation(600, 350);
  setResizable(false);

  addWindowListener(new WindowAdapter() {
   public void windowClosing(WindowEvent e) {
    Window aboutDialog = e.getWindow();
    aboutDialog.dispose();
   }
  });

  pack();
 }

 public void actionPerformed(ActionEvent e) {
  if (e.getSource() == jbnOk) {
   this.dispose();
  }
 }

}

       
 

Reversing a string using stack in java....

Reversing a string using stack in java....

       

here is the code..
import java.util.*;
import java.io.*;
public class Reverse {
 public static void main(String args[]) throws Exception {
  String name = "gaurav";
  int k = name.length();
  Stack ab = new Stack();

  char[] name1 = new char[k];

  for (int i = 0; i < k; i++)
   ab.push(new Character(name.charAt(i)));

  for (int j = 0; j < k; j++)
   name1[j] = ((Character) ab.pop()).charValue();

  for (char s: name1)
   System.out.print(s);

 }
}

       
 

Quicksort implemented using Java......

/*Java program for sorting an array using quicksort ...*/

here is the code ...

       

import java.io.*;
public class Quick {

 public static void Quicksort(int[] arr, int lower, int upper) {
  int i = 0;
  if (lower < upper) {
   i = split(arr, lower, upper);
   Quicksort(arr, lower, i - 1);
   Quicksort(arr, i + 1, upper);
  }
 }

 public static int split(int[] arr, int lower, int upper) {
  int t = 0;
  int p = lower + 1;
  int q = upper;
  try {
   while (p <= q) {

    while (arr[p] < arr[lower])
     p++;

    while (arr[q] > arr[lower])
     q--;
    if (q > p) {
     t = arr[q];
     arr[q] = arr[p];
     arr[p] = t;
    }
   }
  } catch (Exception e) {
   e.printStackTrace();
  }
  t = arr[q];
  arr[q] = arr[lower];
  arr[lower] = t;
  return q;

 }


 public static void main(String args[]) {
  int[] arr = {
   6,
   7,
   9,
   3,
   5,
   10,
   34,
   13
  };
  int lower = 0, upper = arr.length - 1;
  Quicksort(arr, lower, upper);

  for (int k: arr)
   System.out.println(k);

 }
}