Ajay Shilwant Blogs....

04 March 2011

Convert Number to String

Convert Number to String in Java using Swing..... (Editor use: Net Bean)

firstly create new project. in this project add one Java class file and name this file "EnglishNumberToWords.Java"
and copy following line of code in this file.....

*************************Code********************************

package number;
import java.text.DecimalFormat;

public class EnglishNumberToWords {

  private static final String[] tensNames = {
   "",
   " ten",
   " twenty",
   " thirty",
   " forty",
   " fifty",
   " sixty",
   " seventy",
   " eighty",
   " ninety"
  };

  private static final String[] numNames = {
   "",
   " one",
   " two",
   " three",
   " four",
   " five",
   " six",
   " seven",
   " eight",
   " nine",
   " ten",
   " eleven",
   " twelve",
   " thirteen",
   " fourteen",
   " fifteen",
   " sixteen",
   " seventeen",
   " eighteen",
   " nineteen"
  };

  private static String convertLessThanOneThousand(int number) {
   String soFar;

   if (number % 100 < 20){
   soFar = numNames[number % 100];
   number /= 100;
   }
   else {
   soFar = numNames[number % 10];
   number /= 10;

   soFar = tensNames[number % 10] + soFar;
   number /= 10;
   }
   if (number == 0) return soFar;
   return numNames[number] + " hundred" + soFar;
  }

  public static String convert(long number) {
   // 0 to 999 999 999 999
   if (number == 0) { return "zero"; }

   String snumber = Long.toString(number);
   String snumber1 = Long.toString(number);
   // pad with "0"
   String mask = "000000000000";
   String mask1 = "000000000";
   DecimalFormat df = new DecimalFormat(mask);
   DecimalFormat df1 = new DecimalFormat(mask1);

   snumber = df.format(number);
   snumber1 = df1.format(number);

   // XXXnnnnnnnnn
   int billions = Integer.parseInt(snumber.substring(0,3));
   int coror = Integer.parseInt(snumber1.substring(0, 2));

   // nnnXXXnnnnnn
   int millions = Integer.parseInt(snumber.substring(3,6));
   int lakh = Integer.parseInt(snumber1.substring(2,4));
   int thousand = Integer.parseInt(snumber1.substring(4,6));
   int hundred = Integer.parseInt(snumber1.substring(6,9));
   //System.out.println("---1---"+coror+"-------2--------"+lakh+"-----3--------"+thousand+"-------4-------"+hundred);
   String corors;
   switch(coror){
   case 0:
   corors = "";
   break;
   case 1:
   corors = convertLessThanOneThousand(coror)+" corror";
   break;
   default:
   corors = convertLessThanOneThousand(coror)+" corror";

   }
   String result1 = corors;
   String lakhs;
   switch(lakh){
   case 0 :
   lakhs = "";
   break;
   case 1 :
   lakhs = convertLessThanOneThousand(lakh)+" lakh";
   break;
   default:
   lakhs = convertLessThanOneThousand(lakh)+" lakh";

   }
   result1 = result1+lakhs;
   String thou;
   switch(thousand){
   case 0 :
   thou = "";
   break;
   case 1:
   thou =lakhs = convertLessThanOneThousand(thousand)+" thausands";
   break;
   default:
   thou =lakhs = convertLessThanOneThousand(thousand)+" thausands";
   }
   result1 = result1+thou;
   result1 = result1+convertLessThanOneThousand(hundred);

   // nnnnnnXXXnnn
   int hundredThousands = Integer.parseInt(snumber.substring(6,9));
   // nnnnnnnnnXXX
   int thousands = Integer.parseInt(snumber.substring(9,12));

   String tradBillions;
   switch (billions) {
   case 0:
   tradBillions = "";
   break;
   case 1 :
   tradBillions = convertLessThanOneThousand(billions)
   + " billlions ";
   break;
   default :
   tradBillions = convertLessThanOneThousand(billions)
   + " Billions ";
   }
   String result = tradBillions;

   String tradMillions;
   switch (millions) {
   case 0:
   tradMillions = "";
   break;
   case 1 :
   tradMillions = convertLessThanOneThousand(millions)
   + " million ";
   break;
   default :
   tradMillions = convertLessThanOneThousand(millions)
   + " million ";
   }
   result = result + tradMillions;

   String tradHundredThousands;
   switch (hundredThousands) {
   case 0:
   tradHundredThousands = "";
   break;
   case 1 :
   tradHundredThousands = "one thousand ";
   break;
   default :
   tradHundredThousands = convertLessThanOneThousand(hundredThousands)
   + " thousand ";
   }
   result = result + tradHundredThousands;

   String tradThousand;
   tradThousand = convertLessThanOneThousand(thousands);
   result = result + tradThousand;

   // remove extra spaces!
   return result1.replaceAll("^\\s+", "").replaceAll("\\b\\s{2,}\\b", " ");
  }

  /**
   * testing
   * @param args
   */
  public static void main(String[] args) {
   System.out.println("my one"+EnglishNumberToWords.convert(237898555));
   System.out.println("*** " + EnglishNumberToWords.convert(0));
   System.out.println("*** " + EnglishNumberToWords.convert(1));
   System.out.println("*** " + EnglishNumberToWords.convert(16));
   System.out.println("*** " + EnglishNumberToWords.convert(100));
   System.out.println("*** " + EnglishNumberToWords.convert(118));
   System.out.println("*** " + EnglishNumberToWords.convert(200));
   System.out.println("***219 " + EnglishNumberToWords.convert(219));
   System.out.println("*** " + EnglishNumberToWords.convert(800));
   System.out.println("*** " + EnglishNumberToWords.convert(801));
   System.out.println("*** " + EnglishNumberToWords.convert(1316));
   System.out.println("*** " + EnglishNumberToWords.convert(1000000));
   System.out.println("*** " + EnglishNumberToWords.convert(2000000));
   System.out.println("*** " + EnglishNumberToWords.convert(3000200));
   System.out.println("*** " + EnglishNumberToWords.convert(700000));
   System.out.println("*** " + EnglishNumberToWords.convert(9000000));
   System.out.println("*** " + EnglishNumberToWords.convert(9001000));
   System.out.println("*** " + EnglishNumberToWords.convert(123456789));
   System.out.println("*** " + EnglishNumberToWords.convert(2147483647));
   System.out.println("*** " + EnglishNumberToWords.convert(3000000010L));
}
}

****************************************************************

after that create one Java Frame with one Text Box, one Button and labels, design same like as above image

after that at Button Click Event (ActionPerformed event) add following code.....

*************************Code***********************************

int Number = Integer.parseInt(txtNumber.getText());
   String No2String = EnglishNumberToWords.convert(Number)+"";
   txtString.setText(No2String);

in this code assign text box value to a "Number" variable and pass this value to the Function in above code "EnglishNumberToWords.Convert(Number)" and after that print the value

***************************Thanks************************************
Note : this project is available at http://www.planet-source-code.com site

Convert Number to String in Java using Swing..... (Editor use: Net Bean)

07 February 2011

Digital clock by using timer (swing) in Java

Here is a piece of code to build a Java clock, using swing,

        Timer t = new Timer(1000, updateClockAction);
        t.start();

ActionListener updateClockAction = new ActionListener() {
public void actionPerformed(ActionEvent e) {
      // Assumes clock is a custom component
     lblTime.setText(System.currentTimeMillis()+"");
      // OR

      // Assumes clock is a JLabel
      lblTime.setText(new Date().toString());
    }
};

04 February 2011

Digital clock by using Java

Here is a piece of code to build a Java clock, that uses threads, gets the data for time automatically and is not interrupted if you click something else on the window. There are some comments around the code to help you understand what's happening.

import java.awt.*;
import javax.swing.*;
import java.util.*;

class Clock extends JFrame implements Runnable
{
Thread runner; //declare global objects
Font clockFont;

     public Clock()
     {
       super("Java clock");
       setSize( 350, 100);
       setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
       setVisible(true);
       setResizable(false);                             //create window

       clockFont = new Font("Serif", Font.BOLD, 40);    //create font instance

       Container contentArea = getContentPane();
       ClockPanel timeDisplay = new ClockPanel();

       contentArea.add(timeDisplay);                    //add components
       setContentPane(contentArea);
       start();                                         //start thread running

     }

     class ClockPanel extends JPanel
     {
      public void paintComponent(Graphics painter )
        {
        Image pic =
          Toolkit.getDefaultToolkit().getImage("background.jpg");

         if(pic != null)

            painter.drawImage(pic, 0, 0, this);     //create image

//if I didn't use a background image I would have used the setColor and fillRect methods to set background

          painter.setFont(clockFont);                   //create clock components
          painter.setColor(Color.black);
          painter.drawString( timeNow(), 60, 40);
        }
     }

     //get current time
     public String timeNow()
     {
       Calendar now = Calendar.getInstance();
       int hrs = now.get(Calendar.HOUR_OF_DAY);
       int min = now.get(Calendar.MINUTE);
       int sec = now.get(Calendar.SECOND);

       String time = zero(hrs)+":"+zero(min)+":"+zero(sec);

       return time;
     }

     public String zero(int num)
     {
       String number=( num < 10) ? ("0"+num) : (""+num);
       return number;                                    //Add leading zero if needed

     }

     public void start()
     {
       if(runner == null) runner = new Thread(this);
       runner.start();                                  //method to start thread
     }

     public void run()
     {
       while (runner == Thread.currentThread() )
       {
        repaint();
                                                         //define thread task
           try
             {
               Thread.sleep(1000);
             }
              catch(InterruptedException e)
                  {
                    System.out.println("Thread failed");
                  }
       }
     }

     //create main method
     public static void main(String [] args)
     {
       Clock eg = new Clock();
     }
}

17 January 2011

Java Database Connectivity (JDBC Tutorial)

Java Database Connectivity:

JDBC (Java Database Connectivity) is designed to allow users to use SQL(Structured Query Language) to query databases. It makes the tasks of the developers easy as it handles all low-level concerns about particular database types.

JDBC is similar to Microsoft’s ODBC with the plus point “Platform Independence”. To use JDBC, you need to have database driver to communicate with the database. Normally drivers are installed while installing the database. Like if you install MS SQL Server, Oracle or DB2, database drivers will be installed. If you are working with MySQL, PostgreSQL or some third party database, you need to put its driver (Jar fileI into the class path.

JDBC Drivers
            JDBC drivers can be broadly divided into four categories depending upon the driver implementation. The four categories/types are:

            1: JDBC-ODBC Bridge
            2: Native-API/partly Java driver
            3: Net-protocol/all-Java driver
            4: Native-protocol/all-Java driver

I will briefly talk about each type:
            JDBC-OBC bridge driver is pure Java and is include in java.sql.*. The client needs ODBC driver manager and ODBC driver for data source. It is ideal in situations, when ODBC driver is available for the database and is already installed on the client machine.

            Type-2 is Native code driver. It implements native JDBC interfaces using language functions in the DBMS product’s API. Type 2 drivers need platform specific library, so client and server both may run on same host. Type 2 drivers offer better performance than Type 1 drivers.

Type 3 drivers are pure Java drivers and they use middleware network protocol. They need DBMS server to implement the standard protocol to be middleware specific. The advantage is that there is no nee for any vendor database library to be present on client machines. Interesting thing is, there is no JDBC standard network protocol yet.

Type 4 drivers are pure Java drivers and they use vendor specific network protocol. These use DBMS specific network protocol (Oracle SQL Net, etc).
For the beginners, Type 1 drivers are suitable. Users simply have to make a DSN and start interacting with the database.

Using JDBC-ODBC Bridge

The beginners should start with JDBC-ODBC Bridge since it is simple and easy to work with. Consider that you have a database with tables and data and you want to connect to it in order to carry out operations.
First step is to create an ODBC dsn. It is done from Control panel > Data Sources (ODBC).
Now you have to load the JDBC driver. This is done using static method forName(…) of class called Class. Static method forName(…) takes name of the driver as parameter.

Code:

Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");

DriverManager.getConnection() is used to connect to the database. Its signature is as follows:

Code:

static Connection getConnection(String url, String user, String password)

Continue...
31/01/2011

Connection time:

Sometimes, it is interesting to know how much time it takes to connect to the database. The code sample below calculates the time it takes to connect to a database referred by dsn.

Code:

long connection_time;

Date start = new Date(); //get start time

String stUrl_= "jdbc:odbc:myDSN";

connection_ = DriverManager.getConnection(stUrl,"sa","sa");

Date end = new java.util.Date(); //get end time

connection_time = end.getTime()-start.getTime();

Getting the Warnings:

Sometimes it is a wise decision to retrieve the first warning reported by calls on this Connection object. This can be done using getWarnings() method. The code sample below shows how to print all the warnings with their sates and messages.

Code:

Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" ) ;

Connection conn = DriverManager.getConnection( "jdbc:odbc:Database" ) ;

// Print all warnings

for( SQLWarning warn = conn.getWarnings(); warn != null; warn = warn.getNextWarning() )

{

System.out.println( "SQL Warning:" ) ;

System.out.println( "State : " + warn.getSQLState() ) ;

System.out.println( "Message: " + warn.getMessage() ) ;

System.out.println( "Error : " + warn.getErrorCode() ) ;

}

Adding records in the database tables:

Statement object is used to add enteries into the tables. The method used is executeUpdate(…).

Code:

Statement st = conn.createStatement();

st.executeUpdate("INSERT INTO customers VALUES (100, 'Laiq', 'Mr.', 'Paris', 2008)");

Using Resultset:
ResultSet is an interface found in java.sql package. It actually represents a table in the memory containing all the records fetched from the database in result of a query.

Code:

String name, brand ;

float price;

ResultSet rs = stmt.executeQuery("SELECT * FROM customers");

while ( rs.next() ) {

name = rs.getString("name");

brand = rs.getString("brand");

price = rs.getFloat("price");

}

Getting number of rows updated
Statement’s executeUpdate(…) method return no of row modified. So you can easily know how many rows were modified by your update query.

Code:

int rows = stmt.executeUpdate( "UPDATE customer SET

cust_name = ‘Laiq’ WHERE cust_id = 100" ) ;

System.out.println( rows + " Rows modified" ) ;

Java Database Connectivity:

Code:

Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");

DriverManager.getConnection() is used to connect to the database. Its signature is as follows:

Code:

static Connection getConnection(String url, String user, String password)

Continue...
31/01/2011

Code:

long connection_time;

Date start = new Date(); //get start time

String stUrl_= "jdbc:odbc:myDSN";

connection_ = DriverManager.getConnection(stUrl,"sa","sa");

Date end = new java.util.Date(); //get end time

connection_time = end.getTime()-start.getTime();

Code:

Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" ) ;

Connection conn = DriverManager.getConnection( "jdbc:odbc:Database" ) ;

// Print all warnings

for( SQLWarning warn = conn.getWarnings(); warn != null; warn = warn.getNextWarning() )

{

System.out.println( "SQL Warning:" ) ;

System.out.println( "State : " + warn.getSQLState() ) ;

System.out.println( "Message: " + warn.getMessage() ) ;

System.out.println( "Error : " + warn.getErrorCode() ) ;

}

Adding records in the database tables:

Statement object is used to add enteries into the tables. The method used is executeUpdate(…).

Code:

Statement st = conn.createStatement();

st.executeUpdate("INSERT INTO customers VALUES (100, 'Laiq', 'Mr.', 'Paris', 2008)");

Using Resultset:
ResultSet is an interface found in java.sql package. It actually represents a table in the memory containing all the records fetched from the database in result of a query.

Code:

String name, brand ;

float price;

ResultSet rs = stmt.executeQuery("SELECT * FROM customers");

while ( rs.next() ) {

name = rs.getString("name");

brand = rs.getString("brand");

price = rs.getFloat("price");

}

Getting number of rows updated
Statement’s executeUpdate(…) method return no of row modified. So you can easily know how many rows were modified by your update query.

Code:

int rows = stmt.executeUpdate( "UPDATE customer SET

cust_name = ‘Laiq’ WHERE cust_id = 100" ) ;

System.out.println( rows + " Rows modified" ) ;