How to use

canPayLifeCost

method

in

mage.players.Player

@Override
public boolean canPay(Ability ability, UUID sourceId, UUID controllerId, Game game) {
  Player controller = game.getPlayer(controllerId);
  return controller != null && (controller.getLife() < 1 || controller.canPayLifeCost());
}

@Override
public boolean canPay(Ability ability, UUID sourceId, UUID controllerId, Game game) {
  Player controller = game.getPlayer(controllerId);
  return controller != null && (controller.getLife() < 1 || controller.canPayLifeCost());
}

@Override
public boolean canPay(Ability ability, UUID sourceId, UUID controllerId, Game game) {
  Player controller = game.getPlayer(controllerId);
  return controller != null && (controller.getLife() < 1 || controller.canPayLifeCost());
}

@Override
public boolean canPay(Ability ability, UUID sourceId, UUID controllerId, Game game) {
  Player player = game.getPlayer(controllerId);
  if (player != null
      && player.canPayLifeCost()
      && player.getLife() >= 1) {
    return true;
  }
  return false;
}

@Override
public boolean canPay(Ability ability, UUID sourceId, UUID controllerId, Game game) {
  //118.4. If a cost or effect allows a player to pay an amount of life greater than 0,
  //the player may do so only if their life total is greater than or equal to the
  //amount of the payment. If a player pays life, the payment is subtracted from his or
  //her life total; in other words, the player loses that much life. (Players can always pay 0 life.)
  int lifeToPayAmount = amount.calculate(game, ability, null);
  // Paying 0 life is not considered paying any life.
  if (lifeToPayAmount > 0 && !game.getPlayer(controllerId).canPayLifeCost()) {
    return false;
  }
  return game.getPlayer(controllerId).getLife() >= lifeToPayAmount || lifeToPayAmount == 0;
}

@Override
public int getMaxValue(Ability source, Game game) {
  int maxValue = 0;
  Player controller = game.getPlayer(source.getControllerId());
  if (controller != null) {
    // Paying 0 life is not considered paying any life, so paying 0 is still allowed
    if (game.getPlayer(source.getControllerId()).canPayLifeCost()) {
      maxValue = controller.getLife();
    }
  }
  return maxValue;
}

@Override
public boolean pay(Ability ability, Game game, UUID sourceId, UUID controllerId, boolean noMana, Cost costToPay) {
  Player player = game.getPlayer(controllerId);
  if (player == null) {
    return false;
  }
  paid = false;
  manaCost.clearPaid();
  if (manaCost.pay(ability, game, player.getId(), player.getId(), false)
      && player.canPayLifeCost()
      && player.getLife() >= 1
      && lifeCost.pay(ability, game, player.getId(), player.getId(), false)) {
    paid = true;
  }
  return paid;
}

this.canPayLifeCost = player.canPayLifeCost();
this.sacrificeCostFilter = player.getSacrificeCostFilter() != null ? player.getSacrificeCostFilter().copy() : null;
this.loseByZeroOrLessLife = player.canLoseByZeroOrLessLife();

@Override
public boolean apply(Game game, Ability source) {
  Player controller = game.getPlayer(source.getControllerId());
  Player targetPlayer = game.getPlayer(source.getFirstTarget());
  if (controller != null && targetPlayer != null) {
    Card card = targetPlayer.getLibrary().getFromTop(game);
    if (card != null) {
      MageObject sourceObject = game.getObject(source.getSourceId());
      controller.lookAtCards(sourceObject != null ? sourceObject.getName() : "", new CardsImpl(card), game);
      if (!card.isLand()
          && controller.canPayLifeCost()
          && controller.getLife() >= 2
          && controller.chooseUse(Outcome.Neutral, "Pay 2 life to put " + card.getLogName() + " into graveyard?", source, game)) {
        controller.loseLife(2, game, false);
        controller.moveCards(card, Zone.GRAVEYARD, source, game);
      }
      return true;
    }
  }
  return false;
}

Card card = cards.get(cardId, game);
if (card != null) {
  if (controller.canPayLifeCost()
      && controller.getLife() >= 4
      && controller.chooseUse(outcome, "Pay 4 life for " + card.getLogName() + "? (Otherwise it's put on top of your library)", source, game)) {

if (otherPlayer.canPayLifeCost()
    && otherPlayer.getLife() >= 2) {
  PayLifeCost lifeCost = new PayLifeCost(2);