Fixed NPE on game.getState() usage

Mage.Client/src/main/java/mage/client/remote/S3Uploader.java

@@ -4,9 +4,10 @@ import com.amazonaws.AmazonClientException;
 import com.amazonaws.auth.BasicAWSCredentials;
 import com.amazonaws.services.s3.transfer.TransferManager;
 import com.amazonaws.services.s3.transfer.Upload;
-import java.io.File;
 import org.apache.log4j.Logger;
 
+import java.io.File;
+
 public class S3Uploader {
 
     private static final Logger logger = Logger.getLogger(S3Uploader.class);
@@ -18,9 +19,9 @@ public class S3Uploader {
         String accessKeyId = System.getenv("AWS_ACCESS_ID");
         String secretKeyId = System.getenv("AWS_SECRET_KEY");
 
-        if (accessKeyId == null || "".equals(accessKeyId)
+        if (accessKeyId == null || accessKeyId.isEmpty()
-                || secretKeyId == null || "".equals(secretKeyId)
+                || secretKeyId == null || secretKeyId.isEmpty()
-                || existingBucketName == null || "".equals(existingBucketName)) {
+                || existingBucketName == null || existingBucketName.isEmpty()) {
             logger.info("Aborting json log sync.");
             return false;
         }

Mage.Sets/src/mage/cards/c/CabalTherapist.java

@@ -10,7 +10,10 @@ import mage.abilities.effects.OneShotEffect;
 import mage.abilities.effects.common.ChooseACardNameEffect;
 import mage.abilities.effects.common.DoWhenCostPaid;
 import mage.abilities.keyword.MenaceAbility;
-import mage.cards.*;
+import mage.cards.Card;
+import mage.cards.CardImpl;
+import mage.cards.CardSetInfo;
+import mage.cards.Cards;
 import mage.constants.CardType;
 import mage.constants.Outcome;
 import mage.constants.SubType;
@@ -79,10 +82,10 @@ class CabalTherapistDiscardEffect extends OneShotEffect {
         Player targetPlayer = game.getPlayer(targetPointer.getFirst(game, source));
         Player controller = game.getPlayer(source.getControllerId());
         MageObject sourceObject = game.getObject(source.getSourceId());
-        if (targetPlayer == null || controller == null || sourceObject == null) {
+        String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (targetPlayer == null || controller == null || sourceObject == null || cardName == null) {
             return false;
         }
-        String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
         Cards hand = targetPlayer.getHand().copy();
         targetPlayer.revealCards(source, hand, game);
         hand.removeIf(uuid -> {

Mage.Sets/src/mage/cards/c/CabalTherapy.java

@@ -6,10 +6,14 @@ import mage.abilities.costs.common.SacrificeTargetCost;
 import mage.abilities.effects.OneShotEffect;
 import mage.abilities.effects.common.ChooseACardNameEffect;
 import mage.abilities.keyword.FlashbackAbility;
-import mage.cards.*;
+import mage.cards.Card;
+import mage.cards.CardImpl;
+import mage.cards.CardSetInfo;
+import mage.cards.Cards;
 import mage.constants.CardType;
 import mage.constants.Outcome;
 import mage.constants.TimingRule;
+import mage.filter.StaticFilters;
 import mage.game.Game;
 import mage.players.Player;
 import mage.target.TargetPlayer;
@@ -17,7 +21,6 @@ import mage.target.common.TargetControlledCreaturePermanent;
 import mage.util.CardUtil;
 
 import java.util.UUID;
-import mage.filter.StaticFilters;
 
 /**
  * @author jonubuu
@@ -64,10 +67,10 @@ class CabalTherapyEffect extends OneShotEffect {
         Player targetPlayer = game.getPlayer(targetPointer.getFirst(game, source));
         Player controller = game.getPlayer(source.getControllerId());
         MageObject sourceObject = game.getObject(source.getSourceId());
-        if (targetPlayer == null || controller == null || sourceObject == null) {
+        String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (targetPlayer == null || controller == null || sourceObject == null || cardName == null) {
             return false;
         }
-        String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
         Cards hand = targetPlayer.getHand().copy();
         targetPlayer.revealCards(source, hand, game);
         hand.removeIf(uuid -> {

Mage.Sets/src/mage/cards/c/CheeringFanatic.java

@@ -1,7 +1,5 @@
-
 package mage.cards.c;
 
-import java.util.UUID;
 import mage.MageInt;
 import mage.abilities.Ability;
 import mage.abilities.common.AttacksTriggeredAbility;
@@ -10,18 +8,19 @@ import mage.abilities.effects.OneShotEffect;
 import mage.abilities.effects.common.ChooseACardNameEffect;
 import mage.abilities.effects.common.ChooseACardNameEffect.TypeOfName;
 import mage.abilities.effects.common.cost.SpellsCostReductionAllEffect;
-import mage.constants.SubType;
 import mage.cards.CardImpl;
 import mage.cards.CardSetInfo;
 import mage.constants.CardType;
 import mage.constants.Duration;
 import mage.constants.Outcome;
+import mage.constants.SubType;
 import mage.filter.FilterCard;
 import mage.filter.predicate.mageobject.NamePredicate;
 import mage.game.Game;
 
+import java.util.UUID;
+
 /**
- *
  * @author TheElk801
  */
 public final class CheeringFanatic extends CardImpl {
@@ -67,6 +66,9 @@ class CheeringFanaticEffect extends OneShotEffect {
     public boolean apply(Game game, Ability source) {
         new ChooseACardNameEffect(TypeOfName.ALL).apply(game, source);
         String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (cardName == null) {
+            return false;
+        }
         FilterCard filter = new FilterCard();
         filter.add(new NamePredicate(cardName));
         ContinuousEffect effect = new SpellsCostReductionAllEffect(filter, 1);

Mage.Sets/src/mage/cards/c/ChromeReplicator.java

@@ -74,7 +74,7 @@ enum ChromeReplicatorCondition implements Condition {
                 .filter(Objects::nonNull)
                 .map(MageObject::getName)
                 .filter(Objects::nonNull)
-                .filter(s -> !"".equals(s))
+                .filter(s -> !s.isEmpty())
                 .anyMatch(s -> nameMap.compute(s, (x, i) -> i == null ? 1 : Integer.sum(i, 1)) >= 2);
     }
 }

Mage.Sets/src/mage/cards/c/CouncilOfTheAbsolute.java

@@ -93,7 +93,7 @@ class CouncilOfTheAbsoluteReplacementEffect extends ContinuousRuleModifyingEffec
         if (game.getOpponents(source.getControllerId()).contains(event.getPlayerId())) {
             MageObject object = game.getObject(event.getSourceId());
             String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
-            return object != null && CardUtil.haveSameNames(object, cardName, game);
+            return object != null && cardName != null && CardUtil.haveSameNames(object, cardName, game);
         }
         return false;
     }

Mage.Sets/src/mage/cards/d/DeclarationOfNaught.java

@@ -1,12 +1,11 @@
 package mage.cards.d;
 
-import java.util.UUID;
 import mage.abilities.Ability;
 import mage.abilities.common.AsEntersBattlefieldAbility;
 import mage.abilities.common.SimpleActivatedAbility;
 import mage.abilities.costs.mana.ManaCostsImpl;
-import mage.abilities.effects.common.CounterTargetEffect;
 import mage.abilities.effects.common.ChooseACardNameEffect;
+import mage.abilities.effects.common.CounterTargetEffect;
 import mage.cards.CardImpl;
 import mage.cards.CardSetInfo;
 import mage.constants.CardType;
@@ -17,8 +16,9 @@ import mage.game.Game;
 import mage.target.TargetSpell;
 import mage.target.targetadjustment.TargetAdjuster;
 
+import java.util.UUID;
+
 /**
- *
  * @author jeffwadsworth
  */
 public final class DeclarationOfNaught extends CardImpl {
@@ -55,6 +55,9 @@ enum DeclarationOfNaughtAdjuster implements TargetAdjuster {
     public void adjustTargets(Ability ability, Game game) {
         ability.getTargets().clear();
         String chosenName = (String) game.getState().getValue(ability.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (chosenName == null) {
+            return;
+        }
         FilterSpell filterSpell = new FilterSpell("spell named " + chosenName);
         filterSpell.add(new NamePredicate(chosenName));
         TargetSpell target = new TargetSpell(1, filterSpell);

Mage.Sets/src/mage/cards/d/DementiaSliver.java

@@ -79,7 +79,7 @@ class DementiaSliverEffect extends OneShotEffect {
         Player opponent = game.getPlayer(targetPointer.getFirst(game, source));
         MageObject sourceObject = game.getObject(source.getSourceId());
         String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
-        if (opponent != null && sourceObject != null && !cardName.isEmpty()) {
+        if (opponent != null && sourceObject != null && cardName != null && !cardName.isEmpty()) {
             if (!opponent.getHand().isEmpty()) {
                 Cards revealed = new CardsImpl();
                 Card card = opponent.getHand().getRandom(game);

Mage.Sets/src/mage/cards/d/Dispossess.java

@@ -1,7 +1,5 @@
-
 package mage.cards.d;
 
-import java.util.UUID;
 import mage.abilities.Ability;
 import mage.abilities.effects.common.ChooseACardNameEffect;
 import mage.abilities.effects.common.search.SearchTargetGraveyardHandLibraryForCardNameAndExileEffect;
@@ -11,8 +9,9 @@ import mage.constants.CardType;
 import mage.game.Game;
 import mage.target.TargetPlayer;
 
+import java.util.UUID;
+
 /**
- *
  * @author fireshoes
  */
 public final class Dispossess extends CardImpl {
@@ -49,6 +48,9 @@ class DispossessEffect extends SearchTargetGraveyardHandLibraryForCardNameAndExi
     @Override
     public boolean apply(Game game, Ability source) {
         String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (cardName == null) {
+            return false;
+        }
         return super.applySearchAndExile(game, source, cardName, targetPointer.getFirst(game, source));
     }
 

Mage.Sets/src/mage/cards/f/FailureComply.java

@@ -1,7 +1,5 @@
-
 package mage.cards.f;
 
-import java.util.UUID;
 import mage.MageObject;
 import mage.abilities.Ability;
 import mage.abilities.effects.ContinuousRuleModifyingEffectImpl;
@@ -19,6 +17,9 @@ import mage.game.Game;
 import mage.game.events.GameEvent;
 import mage.game.events.GameEvent.EventType;
 import mage.target.TargetSpell;
+import mage.util.CardUtil;
+
+import java.util.UUID;
 
 /**
  * @author spjspj
@@ -72,9 +73,9 @@ class ComplyCantCastEffect extends ContinuousRuleModifyingEffectImpl {
     @Override
     public String getInfoMessage(Ability source, GameEvent event, Game game) {
         MageObject mageObject = game.getObject(source.getSourceId());
-        if (mageObject != null) {
+        String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
-            String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (mageObject != null && cardName != null) {
-            return "You may not cast a card named " + cardName + " (" + mageObject.getIdName() + ").";
+            return "You can't cast a card named " + cardName + " (" + mageObject.getIdName() + ").";
         }
         return null;
     }
@@ -89,9 +90,7 @@ class ComplyCantCastEffect extends ContinuousRuleModifyingEffectImpl {
         String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
         if (game.getOpponents(source.getControllerId()).contains(event.getPlayerId())) {
             MageObject object = game.getObject(event.getSourceId());
-            if (object != null && object.getName().equals(cardName)) {
+            return object != null && CardUtil.haveSameNames(object, cardName, game);
-                return true;
-            }
         }
         return false;
     }

Mage.Sets/src/mage/cards/g/GideonsIntervention.java

@@ -73,9 +73,9 @@ class GideonsInterventionCantCastEffect extends ContinuousRuleModifyingEffectImp
     @Override
     public String getInfoMessage(Ability source, GameEvent event, Game game) {
         MageObject mageObject = game.getObject(source.getSourceId());
-        if (mageObject != null) {
+        String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
-            String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (mageObject != null && cardName != null) {
-            return "You may not cast a card named " + cardName + " (" + mageObject.getIdName() + ").";
+            return "You can't cast a card named " + cardName + " (" + mageObject.getIdName() + ").";
         }
         return null;
     }
@@ -134,7 +134,6 @@ class GideonsInterventionPreventAllDamageEffect extends PreventionEffectImpl {
         MageObject object = game.getObject(event.getSourceId());
         Permanent targetPerm = game.getPermanent(event.getTargetId());
         String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
-
         if (object != null && (event.getType() == GameEvent.EventType.DAMAGE_PLAYER
                 || targetPerm != null && (event.getType() == GameEvent.EventType.DAMAGE_CREATURE
                 || event.getType() == GameEvent.EventType.DAMAGE_PLANESWALKER))) {

Mage.Sets/src/mage/cards/j/JestersScepter.java

@@ -1,8 +1,5 @@
-
 package mage.cards.j;
 
-import java.util.Set;
-import java.util.UUID;
 import mage.MageObject;
 import mage.abilities.Ability;
 import mage.abilities.common.EntersBattlefieldTriggeredAbility;
@@ -14,16 +11,8 @@ import mage.abilities.costs.common.TapSourceCost;
 import mage.abilities.costs.mana.ManaCostsImpl;
 import mage.abilities.effects.AsThoughEffectImpl;
 import mage.abilities.effects.OneShotEffect;
-import mage.cards.Card;
+import mage.cards.*;
-import mage.cards.CardImpl;
+import mage.constants.*;
-import mage.cards.CardSetInfo;
-import mage.cards.Cards;
-import mage.cards.SplitCard;
-import mage.constants.AsThoughEffectType;
-import mage.constants.CardType;
-import mage.constants.Duration;
-import mage.constants.Outcome;
-import mage.constants.Zone;
 import mage.filter.FilterCard;
 import mage.game.ExileZone;
 import mage.game.Game;
@@ -34,14 +23,16 @@ import mage.target.TargetSpell;
 import mage.target.common.TargetCardInExile;
 import mage.util.CardUtil;
 
+import java.util.Set;
+import java.util.UUID;
+
 /**
- *
  * @author jeffwadsworth
  */
 public final class JestersScepter extends CardImpl {
 
     public JestersScepter(UUID ownerId, CardSetInfo setInfo) {
-        super(ownerId,setInfo,new CardType[]{CardType.ARTIFACT},"{3}");
+        super(ownerId, setInfo, new CardType[]{CardType.ARTIFACT}, "{3}");
 
         // When Jester's Scepter enters the battlefield, exile the top five cards of target player's library face down.
         Ability ability = new EntersBattlefieldTriggeredAbility(new JestersScepterEffect(), false);
@@ -213,14 +204,11 @@ class JestersScepterCounterEffect extends OneShotEffect {
     public boolean apply(Game game, Ability source) {
         Spell spell = game.getStack().getSpell(targetPointer.getFirst(game, source));
         if (spell != null) {
-            // In case of Split Card
             String nameOfExiledCardPayment = (String) game.getState().getValue(source.getSourceId() + "_nameOfExiledCardPayment");
             String nameOfExiledCardPayment2 = (String) game.getState().getValue(source.getSourceId() + "_nameOfExiledCardPayment2");
-            if (nameOfExiledCardPayment != null) {
+            if (CardUtil.haveSameNames(spell.getCard(), nameOfExiledCardPayment, game)
-                if (nameOfExiledCardPayment.equals(spell.getCard().getName())
+                    || CardUtil.haveSameNames(spell.getCard(), nameOfExiledCardPayment2, game)) {
-                        || (nameOfExiledCardPayment2 != null) && nameOfExiledCardPayment2.equals(spell.getCard().getName())) {
+                return game.getStack().counter(targetPointer.getFirst(game, source), source.getSourceId(), game);
-                    return game.getStack().counter(targetPointer.getFirst(game, source), source.getSourceId(), game);
-                }
             }
         }
         return false;

Mage.Sets/src/mage/cards/m/MedomaisProphecy.java

@@ -78,7 +78,7 @@ class MedomaisProphecyTriggerEffect extends OneShotEffect {
         String cardName = (String) game.getState().getValue(
                 source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY
         );
-        if (cardName == null || "".equals(cardName)) {
+        if (cardName == null || cardName.isEmpty()) {
             return false;
         }
         game.addDelayedTriggeredAbility(new MedomaisProphecyDelayedTriggeredAbility(cardName), source);

Mage.Sets/src/mage/cards/m/Memoricide.java

@@ -1,6 +1,5 @@
 package mage.cards.m;
 
-import java.util.UUID;
 import mage.abilities.Ability;
 import mage.abilities.Mode;
 import mage.abilities.effects.common.ChooseACardNameEffect;
@@ -11,8 +10,9 @@ import mage.constants.CardType;
 import mage.game.Game;
 import mage.target.TargetPlayer;
 
+import java.util.UUID;
+
 /**
- *
  * @author BetaSteward_at_googlemail.com
  */
 public final class Memoricide extends CardImpl {
@@ -51,6 +51,9 @@ class MemoricideEffect extends SearchTargetGraveyardHandLibraryForCardNameAndExi
     @Override
     public boolean apply(Game game, Ability source) {
         String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (cardName == null) {
+            return false;
+        }
         return super.applySearchAndExile(game, source, cardName, targetPointer.getFirst(game, source));
     }
 

Mage.Sets/src/mage/cards/p/PatternMatcher.java

@@ -20,6 +20,7 @@ import mage.players.Player;
 import mage.target.common.TargetCardInLibrary;
 
 import java.util.List;
+import java.util.Objects;
 import java.util.UUID;
 import java.util.stream.Collectors;
 
@@ -79,7 +80,8 @@ class RegularExpression extends OneShotEffect {
                         source.getControllerId(), source.getSourceId(), game
                 ).stream()
                 .map(Permanent::getName)
-                .filter(s -> !"".equals(s))
+                .filter(Objects::nonNull)
+                .filter(s -> !s.isEmpty())
                 .map(NamePredicate::new)
                 .collect(Collectors.toList());
         FilterCard filter

Mage.Sets/src/mage/cards/s/Shapeshifter.java

@@ -1,9 +1,5 @@
-
 package mage.cards.s;
 
-import java.util.HashSet;
-import java.util.Set;
-import java.util.UUID;
 import mage.MageInt;
 import mage.MageObject;
 import mage.abilities.Ability;
@@ -22,8 +18,11 @@ import mage.game.permanent.Permanent;
 import mage.players.Player;
 import mage.util.CardUtil;
 
+import java.util.HashSet;
+import java.util.Set;
+import java.util.UUID;
+
 /**
- *
  * @author MarcoMarin / HCrescent
  */
 public final class Shapeshifter extends CardImpl {
@@ -116,8 +115,8 @@ class ShapeshifterContinuousEffect extends ContinuousEffectImpl {
     @Override
     public boolean apply(Game game, Ability source) {
         Permanent permanent = game.getPermanent(source.getSourceId());
-        if (permanent != null) {
+        String lastChosen = (String) game.getState().getValue(source.getSourceId().toString() + "_Shapeshifter");
-            String lastChosen = (String) game.getState().getValue(source.getSourceId().toString() + "_Shapeshifter");
+        if (permanent != null && lastChosen != null) {
             int lastChosenNumber = Integer.parseInt(lastChosen);
             permanent.getPower().modifyBaseValue(lastChosenNumber);
             permanent.getToughness().modifyBaseValue(7 - lastChosenNumber);

Mage.Sets/src/mage/cards/s/SlaughterGames.java

@@ -1,7 +1,5 @@
-
 package mage.cards.s;
 
-import java.util.UUID;
 import mage.abilities.Ability;
 import mage.abilities.common.SimpleStaticAbility;
 import mage.abilities.effects.Effect;
@@ -15,14 +13,15 @@ import mage.constants.Zone;
 import mage.game.Game;
 import mage.target.common.TargetOpponent;
 
+import java.util.UUID;
+
 /**
- *
  * @author LevelX2
  */
 public final class SlaughterGames extends CardImpl {
 
     public SlaughterGames(UUID ownerId, CardSetInfo setInfo) {
-        super(ownerId,setInfo,new CardType[]{CardType.SORCERY},"{2}{B}{R}");
+        super(ownerId, setInfo, new CardType[]{CardType.SORCERY}, "{2}{B}{R}");
 
         // Slaughter Games can't be countered.
         Effect effect = new CantBeCounteredSourceEffect();
@@ -60,6 +59,9 @@ class SlaughterGamesEffect extends SearchTargetGraveyardHandLibraryForCardNameAn
     @Override
     public boolean apply(Game game, Ability source) {
         String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (cardName == null) {
+            return false;
+        }
         return super.applySearchAndExile(game, source, cardName, targetPointer.getFirst(game, source));
     }
 

Mage.Sets/src/mage/cards/s/StaffOfTheLetterMagus.java

@@ -130,7 +130,7 @@ class StaffOfTheLetterMagusEffect extends OneShotEffect {
                     for (int i = 0; i < spellName.length(); i++) {
                         char letter = spellName.charAt(i);
                         String chosenLetter = (String) game.getState().getValue(mageObject.getId() + "_letter");
-                        if (Character.isLetter(letter) && Character.toUpperCase(letter) == chosenLetter.charAt(0)) {
+                        if (chosenLetter != null && Character.isLetter(letter) && Character.toUpperCase(letter) == chosenLetter.charAt(0)) {
                             lifegainValue++;
                         }
                     }

Mage.Sets/src/mage/cards/s/StainTheMind.java

@@ -1,7 +1,5 @@
-
 package mage.cards.s;
 
-import java.util.UUID;
 import mage.abilities.Ability;
 import mage.abilities.effects.common.ChooseACardNameEffect;
 import mage.abilities.effects.common.search.SearchTargetGraveyardHandLibraryForCardNameAndExileEffect;
@@ -12,14 +10,15 @@ import mage.constants.CardType;
 import mage.game.Game;
 import mage.target.TargetPlayer;
 
+import java.util.UUID;
+
 /**
- *
  * @author LevelX2
  */
 public final class StainTheMind extends CardImpl {
 
     public StainTheMind(UUID ownerId, CardSetInfo setInfo) {
-        super(ownerId,setInfo,new CardType[]{CardType.SORCERY},"{4}{B}");
+        super(ownerId, setInfo, new CardType[]{CardType.SORCERY}, "{4}{B}");
 
         // Convoke
         this.addAbility(new ConvokeAbility());
@@ -52,6 +51,9 @@ class StainTheMindEffect extends SearchTargetGraveyardHandLibraryForCardNameAndE
     @Override
     public boolean apply(Game game, Ability source) {
         String cardName = (String) game.getState().getValue(source.getSourceId().toString() + ChooseACardNameEffect.INFO_KEY);
+        if (cardName == null) {
+            return false;
+        }
         return super.applySearchAndExile(game, source, cardName, targetPointer.getFirst(game, source));
     }
 

Mage.Sets/src/mage/cards/t/TwinningGlass.java

@@ -1,6 +1,6 @@
 package mage.cards.t;
 
-import java.util.ArrayList;
+import mage.ApprovingObject;
 import mage.abilities.Ability;
 import mage.abilities.common.SimpleActivatedAbility;
 import mage.abilities.costs.common.TapSourceCost;
@@ -12,19 +12,21 @@ import mage.cards.CardSetInfo;
 import mage.constants.CardType;
 import mage.constants.Outcome;
 import mage.constants.Zone;
+import mage.filter.common.FilterNonlandCard;
 import mage.filter.predicate.Predicates;
+import mage.filter.predicate.mageobject.NamePredicate;
 import mage.game.Game;
 import mage.game.permanent.Permanent;
 import mage.game.stack.Spell;
 import mage.players.Player;
+import mage.target.TargetCard;
 import mage.watchers.common.SpellsCastWatcher;
+
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 import java.util.UUID;
 import java.util.stream.Collectors;
-import mage.ApprovingObject;
-import mage.filter.common.FilterNonlandCard;
-import mage.filter.predicate.mageobject.NamePredicate;
-import mage.target.TargetCard;
 
 /**
  * @author jeffwadsworth
@@ -95,7 +97,8 @@ class TwinningGlassEffect extends OneShotEffect {
             }
             List<NamePredicate> predicates = spells.stream()
                     .map(Spell::getName)
-                    .filter(s -> !"".equals(s))
+                    .filter(Objects::nonNull)
+                    .filter(s -> !s.isEmpty())
                     .map(NamePredicate::new)
                     .collect(Collectors.toList());
             FilterNonlandCard filterCard = new FilterNonlandCard("nonland card that was cast this turn");

Mage/src/main/java/mage/filter/predicate/mageobject/NamePredicate.java

@@ -27,6 +27,9 @@ public class NamePredicate implements Predicate<MageObject> {
 
     @Override
     public boolean apply(MageObject input, Game game) {
+        if (name == null) {
+            return false;
+        }
         // If a player names a card, the player may name either half of a split card, but not both. 
         // A split card has the chosen name if one of its two names matches the chosen name.
         if (input instanceof SplitCard) {