java database connectivity Java

// java database connectivity

import java.sql.*;
class database_connectivity
{
  Connection con=null;
  Statement stmt=null;
database_connectivity()
{
  try{
   Class.forName("com.mysql.jdbc.Driver");
    con=(Connection)DriverManager.getConnection("jdbc:mysql://localhost/ict","root","admin");
    //JOptionPane.showMessageDialog( "cool");
    System.out.println("Connected");
    stmt=(Statement) con.createStatement();
  }catch(Exception e)
  {
     System.out.println(e);
  }
  //now inserting data into emp table
  int id=Integer.parseInt(txt1.getText());100;
  String name="abcd";
  double salary=40000;

  try{
  for(int i=1;i<5;i++)
 
 // String sql=;
  {
  stmt.executeUpdate("insert into emp values("+i+",'"+name+"',"+salary+")");
  } 
  System.out.println("Successfully Inserted.");

  }catch(Exception ee)
  {
      System.out.println(ee);
  }
}
public static void main(String[] arg)
{
database_connectivity cc=new database_connectivity();
}
}