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package cv1;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/**
 *
 * @author xsevcikj
 */
public class Cv1 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws ClassNotFoundException, SQLException {
        Statement st = connect();
        select(st);
        count(st);
        Double cena = cenaKnihy("asgfg", st);
        System.out.println(cena);
        zlava("hahabebe", st);
    }

    public static Statement connect() throws ClassNotFoundException, SQLException{
        Class.forName("org.apache.derby.jdbc.ClientDriver");
        Connection con = DriverManager.getConnection("jdbc:derby://localhost:1527/sample", "app", "app");
        Statement st = con.createStatement();
        return st;
    }


    public static void select(Statement st) throws SQLException{
        ResultSet rs = st.executeQuery("SELECT * FROM APP.KNIHA");
        while (rs.next()){
            System.out.println(rs.getString(1));
        }
    }

    public static void count(Statement st) throws SQLException{
        ResultSet rs = st.executeQuery("SELECT count(*) FROM kniha");
        while (rs.next()){
            System.out.println("" + rs.getInt(1));
        }
    }

    public static Double cenaKnihy(String meno, Statement st) throws SQLException{
        ResultSet rs = st.executeQuery("SELECT cena FROM kniha WHERE nazov='"+meno+"'");
        double cena = -1.00;
        if (!rs.next()){
            System.out.println("Nemam taku knihu");
            return cena;
        }

        return rs.getDouble(1);
    }

    public static boolean pridajKnihu(String nazov, double cena, Statement st) throws SQLException{
        ResultSet rs = st.executeQuery("SELECT * FROM kniha WHERE nazov='"+nazov+"'");
        if (!rs.next()){
            return false;
        }
        st.executeUpdate("INSERT INTO kniha " + "VALUES ('"+nazov+"', '"+cena+"')");
        return true;
    }

    public static void zlava(String nazov, Statement st) throws SQLException{
        Connection con = DriverManager.getConnection("jdbc:derby://localhost:1527/sample", "app", "app");
        PreparedStatement ps = con.prepareStatement("UPDATE kniha SET cena = ? WHERE nazov = ?");
        ResultSet rs = st.executeQuery("SELECT cena FROM kniha WHERE nazov='"+nazov+"'");
        if (rs.next()){
            Double cena = rs.getDouble(1);
            cena = cena * 0.8;
            ps.setDouble(1, cena);
            ps.setString(2, nazov);
            ps.executeUpdate();
            ps.close();
        }

    }
}