How to create a vCard in Java

import java.io.*;
 
public class Vcard{
 
    public static void main(String[] args) throws IOException{
 
      File f=new File("contact.vcf");
      FileOutputStream fop=new FileOutputStream(f);
      
      if(f.exists()){
      String str="BEGIN:VCARD\n" +
                 "VERSION:4.0\n" +
                 "N:Gump;Forrest;;;\n" +
                 "FN:Forrest Gump\n"+
                 "ORG:Bubba Gump Shrimp Co.\n"+
                 "TITLE:Shrimp Man\n"+
                 "TEL;TYPE=work,voice;VALUE=uri:tel:+1-111-555-1212\n"+
                 "TEL;TYPE=home,voice;VALUE=uri:tel:+1-404-555-1212\n"+
   "EMAIL:forrestgump@example.com\n"+
            "REV:20080424T195243Z\n"+
                 "END:VCARD";
          fop.write(str.getBytes());
          //Now read the content of the vCard after writing data into it
          BufferedReader br = null;
          String sCurrentLine;
          br = new BufferedReader(new FileReader("contact.vcf"));
          while ((sCurrentLine = br.readLine()) != null) {
  System.out.println(sCurrentLine);
   }
          //close the output stream and buffer reader
          fop.flush();
          fop.close();
          System.out.println("The data has been written");
          }
 
          else
            System.out.println("This file does not exist");
    }
  }

Get user input using java swing and write to text file

import java.io.*;
import javax.swing.JOptionPane;
import java.util.Scanner;

public class ClientList
{
public static void main (String args[]) throws IOException
	{
	 // Main class ClientList creates Clients.txt file that is to be opened up and appended whenever clients are to be added
		FileWriter outFile = new FileWriter("Clients.txt");
		BufferedWriter outStream = new BufferedWriter(outFile);
		String outString = "Client Listing";
		outStream.write(outString);
		outStream.newLine();
		outStream.close();
		System.out.println("Clients.txt is created\n");

	 // "Primitive" menu asks user what he/she wants to do and accepts commands via keyboard scanner
		Scanner menu = new Scanner(System.in);
		System.out.println("Welcome to ClientList");
		System.out.println();
		System.out.println("To add clients to the file, enter 1");
		System.out.println("To open file and view its contents, enter 2");
	 //	System.out.println("To search for a client in the file, enter 3");
		int command = menu.nextInt();

		switch (command)
		{
		case 1: Clients client = new Clients();
				client.enterData();
	    		break;
	    case 2: Clients client2 = new Clients();
	    		client2.getClients();
	    		break;
	 // case 3: Clients client = new Clients();
	 //			client.searchClients();
	 //   		break;
	    default: System.out.println("Doesn't exist!");
	    		 System.out.print("Enter a valid number ===> ");
	    	     int l = menu.nextInt();
	    	     break;
		}
	}
}

class Clients
	{
	 // Initializing variables for client data
		String firstName;
 		String lastName;
 		String age;
 		String height;
 		String weight;
 		String startDate;
 		String phNum;

		public void enterData() throws IOException
 		{
 	 // Initializing boolean variable isValid to check the number of clients user inputs
 	 // and make sure it really IS a number
 		boolean isValid = false;
 		String number;

 	 // Ask user how many clients he/she wishes to enter data for
 	 	do
 	 	{
		number = JOptionPane.showInputDialog("Enter the number of clients you wish to save:");
	 // Loop to check what the user entered against the allowed charcters (only numbers between 0 and 9 allowed)
		if (number.matches("[0-9]*"))
 	 	{
        isValid = true;
        }
        else
        {
        isValid = false;
        }
 	 	}
 	 	while (isValid != true); // Keeps prompting user for a number until a valid number between 0 and 9 is entered
 	 // Finally, parse String number and change to an integer for use in data input loop
		int numOfClients = Integer.parseInt(number);

	 // Data input prompts are put into a loop that repeats until data for all clients is entered
		for (int k = 0; k 

How to iterate throught a Map

//Declare a map object
Map mapObj = new HashMap();
//iterate through the map objects elements one by one 
for (Map.Entry entry : mapObj.entrySet()) {

       System.out.println(entry.getKey() + ": " + entry.getValue());

    }

how to convert Byte[] array to String in Java

public class ByteToString
{    
	public static void main(String[] args) {
 
		    String example = "This is an example";
		    byte[] bytes = example.getBytes();
 
		    System.out.println("Text : " + example);
		    System.out.println("Text in Byte Format] : " + bytes);
		    System.out.println("Text in Byte Format] : " + bytes.toString());
 
		    String s = new String(bytes);
		    System.out.println("Text converted : " + s);
 
 
	}
}

Java program to insert image into database

This is a simple java program used to inject an image into the mysql database:

import java.sql.*;
import java.io.*;

public class insertImg{
    public static void main(String[] args) {

        System.out.println("Insert Image Example!");
        String driverName = "com.mysql.jdbc.Driver";
        String url = "jdbc:mysql://localhost:3306/";
        String dbName = "hibernatetutorial";
        String userName = "root";
        String password = "root";
        Connection con = null;

        try {
            Class.forName(driverName);
            con = DriverManager.getConnection(url+dbName,userName,password);
            Statement st = con.createStatement();

            File imgfile = new File("images.jpg");
            FileInputStream fin = new FileInputStream(imgfile);

            PreparedStatement pre = con.prepareStatement("insert into Image values(?,?,?)");
            pre.setInt(1,5);
            pre.setString(2,"Durga");
            pre.setBinaryStream(3,fin,(int)imgfile.length());
            pre.executeUpdate();

            System.out.println("Inserting Successfully!");

            pre.close();
            con.close();  

        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
    }
} 

How to extract a war file

Download 7-zip and extract it!!simple..

Retrieve and Store BLOB from/to MySQL in Java awt

This post shows you how to insert an image into MySQL database through Java Step 1 : Open MySQL client Step 2 : Execute the following query

CREATE TABLE IF NOT EXISTS `image` (

IMG blob,

IMG_ID int NOT NULL AUTO_INCREMENT,

PRIMARY KEY (`IMG_ID`)

)

Source code -----------

import java.awt.event.ActionEvent;

import java.sql.*; 
import java.awt.Graphics;

import java.awt.event.ActionListener;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import javax.imageio.ImageIO;

import javax.swing.JButton;

import javax.swing.JFileChooser;

import javax.swing.JFrame;

import javax.swing.JOptionPane;

import javax.swing.JPanel;

/**

*

* @author mustaq

*/

public class ImagePanel extends JPanel implements ActionListener {

JButton browse;

Connection con = null;

public ImagePanel() {

con = this.getConnection();

browse = new JButton("Browse");

browse.addActionListener(this);

this.add(browse);

}

public Connection getConnection() {

try {

// Creating connection to DB

Class.forName("com.mysql.jdbc.Driver");

String url = "jdbc:mysql://localhost:3306/image";

Connection c = DriverManager.getConnection(url,"root","");

return c;

}

catch(Exception ex) {

System.out.println(ex.getMessage());

return null;

}

}

public void imageWrite(File file) {

try {

FileInputStream io = new FileInputStream(file);

String query = "insert into image(IMG) values(?)";

java.sql.PreparedStatement stmt = con.prepareStatement(query);

stmt.setBinaryStream(1, (InputStream)io,(int)file.length());

stmt.executeUpdate();

}

catch(Exception ex) {

System.out.println(ex.getMessage());

}

}

public BufferedImage getImageById(int id) {

String query = "select IMG from image where IMG_ID = ?";

BufferedImage buffimg = null;

try {

PreparedStatement stmt = con.prepareStatement(query);

stmt.setInt(1,id);

ResultSet result = stmt.executeQuery();

result.next();

InputStream img = result.getBinaryStream(1); // reading image as InputStream

buffimg= ImageIO.read(img); // decoding the inputstream as BufferedImage

}

catch(Exception ex) {

System.out.println(ex.getMessage());

}

return buffimg;

}

@Override

public void paint(Graphics g) {

BufferedImage img = this.getImageById(5) ; // pass valid IMG_ID

if(img != null)

g.drawImage(img, 70, 20, this); 

}

public static void main(String[] args) {

JFrame frame = new JFrame("ImagePanel Demo");

ImagePanel imgPanel = new ImagePanel();

frame.setVisible(true);

frame.setSize(600, 400);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.getContentPane().add(imgPanel);

}

public void actionPerformed(ActionEvent e) {

JFileChooser chooser = new JFileChooser();

int returnVal = chooser.showOpenDialog(null);

File file = null;

if(returnVal == JFileChooser.APPROVE_OPTION) {

file = chooser.getSelectedFile(); // path to image

this.imageWrite(file); // inserting image into database

JOptionPane.showMessageDialog(this, "Image inserted.", "ImageDemo", JOptionPane.PLAIN_MESSAGE);

this.repaint();

}

}

}