commands-

if (cmd.equals("auth") && input.length() > 0) {

				boolean b = SQL.hasVoted(c, input,
						c.connectedFrom);
				if (b || c.voted) {

					c.lastVoted = System.currentTimeMillis();
					c.voted = true;
					c.getDH().sendDialogues(525, 251);

				} else {
					c.sendMessage("Auth code not valid.");
					return;
				}
				return;

			}


Anywhere - I used a SQL.java class

public static boolean hasVoted(Client c, String auth, String ip) {
		PreparedStatement ps = null;
		try {
			Class.forName("com.mysql.jdbc.Driver").newInstance();
			con = DriverManager.getConnection("jdbc:mysql://localhost/vote",
					"root", "");
			ps = con.prepareStatement("SELECT * FROM votes WHERE authcode = ? AND used = '0' LIMIT 1");
			ps.setString(1, auth);
			ResultSet results = ps.executeQuery();
			if (results.next()) {
				ps.close();
				ps = con.prepareStatement("UPDATE votes SET used = '1' WHERE authcode = ?");
				ps.setString(1, auth);
				ps.executeUpdate();
				return true;
			} else {
				return false;
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				ps.cancel();
				con.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
		return false;
	}