import java.sql.*;

public class DBConnection {
private Connection connection;
private Statement statement;
private ResultSet resultSet;

private PreparedStatement preparedStatement;


public void connection() throws ClassNotFoundException, SQLException {

    Class.forName("com.mysql.jdbc.Driver"); //podajemy nazwe sterownika dla konkretnej bazy danych(wyrzuca wyjatek)
    connection=DriverManager.getConnection("jdbc:mysql://localhost:3306/test3","root",""); //podajemy sciezke do bazy danych, metoda getConnection zwraca connection

}

public void show() throws SQLException {

 statement=connection.createStatement();//zapytanie jest realizowane za pomoca interfesju Statement, mozemy zdefiniowac i wykonac zapytanie
 //preparedStatement=connection.prepareStatement("SELECT * FROM STUDENT")
    resultSet=statement.executeQuery("SELECT * FROM STUDENT"); //metoda executeQuery wykonuje zapytanie i wynik zwraca w postaci obiektu ResultSet(iterator ktory pozwala iterowac po kolejnych wierszach wyniku)
 // resultSet=preparedStatement.executeQuery();
    while(resultSet.next()){

        System.out.print(resultSet.getString("ID")+" - "+resultSet.getString("NAME")+" - "+ resultSet.getString("SURNAME")+" - "+resultSet.getString("AGE")+"\n");

    }
}
 public void addRecord(int id,String name,String surname,String age) throws SQLException {

    preparedStatement=connection.prepareStatement("INSERT INTO STUDENT VALUES(?,?,?,?)");
     preparedStatement.setInt(1,id); //ktory parametr , ktora wartosc
     preparedStatement.setString(2,name);
     preparedStatement.setString(3,surname);
     preparedStatement.setString(4,age);
     preparedStatement.executeUpdate();
     System.out.print(" record inserted"+"\n");


 }


public void deleteRecord(int id ) throws SQLException {
preparedStatement=connection.prepareStatement("DELETE FROM STUDENT WHERE ID=(?)");
preparedStatement.setInt(1,id);
preparedStatement.executeUpdate();
//System.out.print("record deleted"+"\n");



}

public void closeConnection() throws SQLException {
resultSet.close();
statement.close();
connection.close();




}


}