import java.sql.*;

public class MyDBConnection {
   
    private Connection myConnection;
    // JDBC driver name and database URL
    static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";  
    static final String DB_URL = "jdbc:mysql://localhost:3306/myDB";
    
    //  Database credentials
    static final String USER = "UserName";
    static final String PASS = "Password";
    
    /** Creates a new instance of MyDBConnection */
    public MyDBConnection() {
        init();
    }

    public void init(){
    
       try{
        //Register JDBC driver
        Class.forName(JDBC_DRIVER);
        
        //Open a connection
        myConnection=DriverManager.getConnection(DB_URL,USER,PASS);                
        }
        catch(Exception e){
            System.out.println("Failed to get connection");
            e.printStackTrace();
        }
    }    
    
    public Connection getMyConnection(){
        return myConnection;
    }   
    
    public void close(ResultSet rs){        
        if(rs !=null){
            try{
               rs.close();
            }
            catch(Exception e){}        
        }
    }
    
     public void close(java.sql.Statement stmt){
        
        if(stmt !=null){
            try{
               stmt.close();
            }
            catch(Exception e){}        
        }
    }
     
    public void destroy(){
  
        if(myConnection !=null){    
            try{
                myConnection.close();
            }catch(Exception e){}       
        }
    }
    
}

try{
    String sql="SELECT * FROM `priceoil`;";
    mdbcon= new MyDBConnection();
    conn=mdbcon.getMyConnection();
    pst=conn.prepareStatement(sql);
    rs=pst.executeQuery();
    while (rs.next())
    {
        int k=rs.getInt("id");
        System.out.println("HELLO OK DB "+k);           
    }                
    mdbcon.close(rs);
}catch(SQLException e){e.printStackTrace();}