JDBC CONNECTIVITY IN JAVA

•  MysqlCon.file

import java.sql.*;

class MysqlCon{

public static void main(String args[]){

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

Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/javadb","root","");
Statement stmt=con.createStatement();

ResultSet rs=stmt.executeQuery("select * from emp");

while(rs.next())
System.out.println(rs.getInt(1)+"  "+rs.getString(2)+"  "+rs.getString(3));

con.close();

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

}
}

• JDBCINSETDEMO.JAVA

import java.sql.*;
import java.util.Scanner;

public class JdbcInsertDemo
{
public static void main(String[] args) throws Exception
{
String dbURL = "jdbc:mysql://localhost:3306/javadb";
String username = "root";
String password = "";
try
{
Class.forName("com.mysql.jdbc.Driver");

Connection conn = DriverManager.getConnection(dbURL, username, password);
String sql = "INSERT INTO Users (username, password, fullname, email) VALUES (?, ?, ?, ?)";
PreparedStatement statement = conn.prepareStatement(sql);
Scanner input = new Scanner(System.in);
System.out.println("Enter the Username");
String uname = input.next();
System.out.println("Enter the Password");
String pwd = input.next();
System.out.println("Enter the FullName");
String fname = input.next();
System.out.println("Enter the Email ");
String email = input.next();
statement.setString(1, uname);
statement.setString(2, pwd);
statement.setString(3, fname);
statement.setString(4, email);
int rowsInserted = statement.executeUpdate();
if (rowsInserted > 0)
{
System.out.println("A new user was inserted successfully!");
}
}
      catch (SQLException ex)
{
   ex.printStackTrace();
}
}
}

• JDBCUPDATEDEMO.JAVA

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.SQLException;

import java.util.Scanner;

/**

 * A sample program that demonstrates how to execute SQL UPDATE statement

 * using JDBC.

 * @author www.codejava.net

 *

 */

public class JdbcUpdateDemo {

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

 {

String dbURL = "jdbc:mysql://localhost:3306/javadb";

String username = "root";

String password = "";

try {

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

Connection conn = DriverManager.getConnection(dbURL, username, password);

String sql = "UPDATE Users SET password=?, fullname=?, email=? WHERE username=?";

System.out.println("Enter usename you have to update=");

Scanner input = new Scanner(System.in);

String uname = input.next();

PreparedStatement statement = conn.prepareStatement(sql);

statement.setString(1, uname);

statement.setString(2, "William");

statement.setString(3, "bill@gates");

statement.setString(4, "bill");

int rowsUpdated = statement.executeUpdate();

if (rowsUpdated > 0) {

System.out.println("An existing user was updated successfully!");

}

} catch (SQLException ex) {

ex.printStackTrace();

}

}

}

• JDBCDELETEDEMO.JAVA

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.SQLException;

import java.util.Scanner;

/**

 * A sample program that demonstrates how to execute SQL DELETE statement

 * using JDBC. 

 * @author www.codejava.net

 *

 */

public class JdbcDeleteDemo {

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

{

String dbURL = "jdbc:mysql://localhost:3306/javadb";

String username = "root";

String password = "";

try  {

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

Connection conn = DriverManager.getConnection(dbURL, username, password)

String sql = "DELETE FROM Users WHERE username=?";

Scanner input = new Scanner(System.in);

System.out.println("Enter the Username");

String uname = input.next();

PreparedStatement statement = conn.prepareStatement(sql);

statement.setString(1, uname);

int rowsDeleted = statement.executeUpdate();

if (rowsDeleted > 0) {

System.out.println("A user was deleted successfully!");

}

} catch (SQLException ex) {

ex.printStackTrace();

}

}

}

• JDBCSELECTDEMO.JAVA

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

/**

 * A sample program that demonstrates how to execute SQL SELECT statement

 * using JDBC. 

 * @author www.codejava.net

 *

 */

public class JdbcSelectDemo {

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

 {

String dbURL = "jdbc:mysql://localhost:3306/javadb";

String username = "root";

String password = "";

try {

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

Connection conn = DriverManager.getConnection(dbURL, username, password);

String sql = "SELECT * FROM Users";

Statement statement = conn.createStatement();

ResultSet result = statement.executeQuery(sql);

int count = 0;

while (result.next()){

String name = result.getString(2);

String pass = result.getString(3);

String fullname = result.getString("fullname");

String email = result.getString("email");

String output = "User #%d: %s - %s - %s - %s";

System.out.println(String.format(output, ++count, name, pass, fullname, email));

}

} catch (SQLException ex) {

ex.printStackTrace();

}

}

}