Connection c = null;
      try {
         ******Class.forName("oracle.jdbc.driver.OracleDriver");********
         c = DriverManager
            .getConnection("jdbc:postgresql://localhost:5432/postgres",
            "postgres", "199591");
      } catch (Exception e) {
         e.printStackTrace();
         System.err.println(e.getClass().getName()+": "+e.getMessage());
         System.exit(0);
      }
      System.out.println("Opened database successfully");