import java.sql.*;

class Mysql {
	String host = "localhost";
	String port = "3306";
	String db = "sargazrt";
	String user = "sargazrt";
	String pass = "titok";
	public Connection connect() {
		Connection conn = null;
		try {
			conn = tryConnect();
		}catch(SQLException ex) {
			System.err.println("Hiba az adatbázishoz kapcsolódás során!");
		}
		return conn;
	}
	public Connection tryConnect() throws SQLException {
		Connection conn = null;
		String url = "jdbc:mysql://" + host + ":" + port + "/"+ db;
		conn = DriverManager.getConnection(url, user, pass);
		return conn;
	}
	public void close(Connection conn) {
		try {
			tryClose(conn);
		}catch(SQLException ex) {
			System.err.println("Hiba az adatbázis bezárása során!");
		}
	}
	public void tryClose(Connection conn) throws SQLException {
		conn.close();
	}
	public ResultSet query(Connection conn, String sql) {
		ResultSet rs = null;
		try {
			rs = tryQuery(conn, sql);
		}catch(SQLException ex) {
			System.err.println("Hiba a lekérdezés során");
		}
		return rs;
	}
	public ResultSet tryQuery(Connection conn, String sql) throws SQLException {
		ResultSet rs = null;		
		Statement stmt = conn.createStatement();		
		return stmt.executeQuery(sql);
	}
}


class Program01 {
	public static void main(String[] args) {
		System.out.println("MySQL kapcsolódás...");
		Mysql mysql = new Mysql();
		Connection conn = mysql.connect();
		String sql = "select * from Dolgozok";
		ResultSet rs = mysql.query(conn, sql);		
		
		try {
			while(rs.next()) {
				System.out.printf("%s %s\n", 
					rs.getString("nev"),
					rs.getString("telepules")
				);				
			}
		}catch(SQLException ex) { 
			System.err.println("Hiba az adatok kinyerése során!");
		}
		mysql.close(conn);
	}
}