jass.addPlayer(this.player4, 3);
jass.start(this.player1);
jass.setTrumpf(CardColor.HERZ, jass.getCurrentPlayer());
IPlayer starter = jass.getRule().getStartPlayer();
List<IPlayer> players = jass.getPlayers();
IPlayer nextPlayer;
if (starter.equals(players.get(players.size() - 1))) {
nextPlayer = players.get(0);
} else {
nextPlayer = players.get(players.indexOf(starter) + 1);