package consoledb;
 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
 
public class Main {
    public static void main(String[] args) {
       Connection connection;
       Statement stmt;
       ResultSet rs;
       String errMessage = null;
       try{
           Class.forName("org.postgresql.Driver").newInstance();
           connection = DriverManager.getConnection(
                   "jdbc:postgresql://localhost:5432/timetable_v.0.083b", "postgres", "pass");
           String query = "select * from klass";
           stmt = connection.createStatement();
           rs = stmt.executeQuery(query);
           System.out.println(connection.isClosed());
           try{
              while(rs.next()){
                 System.out.println( rs.getString(1)
                         + "   \t" + rs.getString(2)
                         + "   \t" + rs.getString(3));
              }
              rs.close();
           } catch (SQLException e) {
               errMessage = e.getMessage();
               System.out.println(errMessage);
             }
       } catch (Exception e) {
           errMessage = e.getMessage();
           System.out.println(errMessage);
         }
       }
    }