More SonarQube detected bugs fixed:

- Use try-with-resources in AutoCloseable objects.
- End this switch case with an unconditional break, return or throw statement.
- A "NullPointerException" could be thrown.
- Use the "equals" method if value comparison was intended.
- Correct this "&" to "&&".

forge-ai/src/main/java/forge/ai/AiCardMemory.java

@@ -150,12 +150,15 @@ public class AiCardMemory {
      */
     public boolean isRememberedCardByName(String cardName, MemorySet set) {
         Set<Card> memorySet = getMemorySet(set);
-        Iterator<Card> it = memorySet.iterator();
 
-        while (it.hasNext()) {
+        if (memorySet != null) {
-            Card c = it.next();
+            Iterator<Card> it = memorySet.iterator();
-            if (c.getName().equals(cardName)) {
+
-                return true;
+            while (it.hasNext()) {
+                Card c = it.next();
+                if (c.getName().equals(cardName)) {
+                    return true;
+                }
             }
         }
 
@@ -174,12 +177,15 @@ public class AiCardMemory {
      */
     public boolean isRememberedCardByName(String cardName, MemorySet set, Player owner) {
         Set<Card> memorySet = getMemorySet(set);
-        Iterator<Card> it = memorySet.iterator();
 
-        while (it.hasNext()) {
+        if (memorySet != null) {
-            Card c = it.next();
+            Iterator<Card> it = memorySet.iterator();
-            if (c.getName().equals(cardName) && c.getOwner().equals(owner)) {
+
-                return true;
+            while (it.hasNext()) {
+                Card c = it.next();
+                if (c.getName().equals(cardName) && c.getOwner().equals(owner)) {
+                    return true;
+                }
             }
         }
 
@@ -197,7 +203,12 @@ public class AiCardMemory {
         if (c == null)
             return false;
 
-        getMemorySet(set).add(c);
+        Set<Card> memorySet = getMemorySet(set);
+
+        if (memorySet != null) {
+            memorySet.add(c);
+        }
+
         return true;
     }
 
@@ -216,7 +227,12 @@ public class AiCardMemory {
             return false;
         }
 
-        getMemorySet(set).remove(c);
+        Set<Card> memorySet = getMemorySet(set);
+
+        if (memorySet != null) {
+            memorySet.remove(c);
+        }
+
         return true;
     }
 
@@ -229,12 +245,15 @@ public class AiCardMemory {
      */
     public boolean forgetAnyCardWithName(String cardName, MemorySet set) {
         Set<Card> memorySet = getMemorySet(set);
-        Iterator<Card> it = memorySet.iterator();
 
-        while (it.hasNext()) { 
+        if (memorySet != null) {
-            Card c = it.next();
+            Iterator<Card> it = memorySet.iterator();
-            if (c.getName().equals(cardName)) {
+
-                return forgetCard(c, set);
+            while (it.hasNext()) {
+                Card c = it.next();
+                if (c.getName().equals(cardName)) {
+                    return forgetCard(c, set);
+                }
             }
         }
         
@@ -251,12 +270,15 @@ public class AiCardMemory {
      */
     public boolean forgetAnyCardWithName(String cardName, MemorySet set, Player owner) {
         Set<Card> memorySet = getMemorySet(set);
-        Iterator<Card> it = memorySet.iterator();
 
-        while (it.hasNext()) { 
+        if (memorySet != null) {
-            Card c = it.next();
+            Iterator<Card> it = memorySet.iterator();
-            if (c.getName().equals(cardName) && c.getOwner().equals(owner)) {
+
-                return forgetCard(c, set);
+            while (it.hasNext()) {
+                Card c = it.next();
+                if (c.getName().equals(cardName) && c.getOwner().equals(owner)) {
+                    return forgetCard(c, set);
+                }
             }
         }
 
@@ -269,14 +291,16 @@ public class AiCardMemory {
      * @return true, if the given memory set contains no remembered cards.
      */
     public boolean isMemorySetEmpty(MemorySet set) {
-        return getMemorySet(set).isEmpty();
+        return set == null ? true : getMemorySet(set).isEmpty();
     }
     
     /**
      * Clears the given memory set.
      */
     public void clearMemorySet(MemorySet set) {
-        getMemorySet(set).clear();
+        if (set != null) {
+            getMemorySet(set).clear();
+        }
     }
 
     /**

forge-ai/src/main/java/forge/ai/AiController.java

@@ -658,7 +658,7 @@ public class AiController {
         AiCardMemory.MemorySet memSet;
         if (phaseType == null && forNextSpell) {
             memSet = AiCardMemory.MemorySet.HELD_MANA_SOURCES_FOR_NEXT_SPELL;
-        } else {
+        } else if (phaseType != null) {
             switch (phaseType) {
                 case MAIN2:
                     memSet = AiCardMemory.MemorySet.HELD_MANA_SOURCES_FOR_MAIN2;

forge-ai/src/main/java/forge/ai/ComputerUtil.java

@@ -1612,7 +1612,7 @@ public class ComputerUtil {
         }
 
         if (saviourApi == ApiType.PutCounter || saviourApi == ApiType.PutCounterAll) {
-            if (saviour.getParam("CounterType").equals("P1P1")) {
+            if (saviour != null && saviour.getParam("CounterType").equals("P1P1")) {
                 toughness = AbilityUtils.calculateAmount(saviour.getHostCard(), saviour.getParam("CounterNum"), saviour);
             } else {
                 return threatened;

forge-ai/src/main/java/forge/ai/ComputerUtilCard.java

@@ -926,7 +926,7 @@ public class ComputerUtilCard {
             }
             else if (logic.equals("MostProminentInComputerDeckButGreen")) {
             	List<String> prominence = ComputerUtilCard.getColorByProminence(CardLists.filterControlledBy(game.getCardsInGame(), ai));
-            	if (prominence.get(0) == MagicColor.Constant.GREEN) {
+            	if (prominence.get(0).equals(MagicColor.Constant.GREEN)) {
                     chosen.add(prominence.get(1));
             	} else {
                     chosen.add(prominence.get(0));
@@ -1878,7 +1878,7 @@ public class ComputerUtilCard {
 
             // A special case which checks that this creature will attack if it's the AI's turn
             if (needsToPlay.equalsIgnoreCase("WillAttack")) {
-                if (game.getPhaseHandler().isPlayerTurn(sa.getActivatingPlayer())) {
+                if (sa != null && game.getPhaseHandler().isPlayerTurn(sa.getActivatingPlayer())) {
                     return ComputerUtilCard.doesSpecifiedCreatureAttackAI(sa.getActivatingPlayer(), card) ?
                         AiPlayDecision.WillPlay : AiPlayDecision.BadEtbEffects;
                 } else {

forge-ai/src/main/java/forge/ai/GameState.java

@@ -631,7 +631,9 @@ public abstract class GameState {
         // Note: triggers may fire during combat declarations ("whenever X attacks, ...", etc.)
         if (newPhase == PhaseType.COMBAT_DECLARE_ATTACKERS || newPhase == PhaseType.COMBAT_DECLARE_BLOCKERS) {
             boolean toDeclareBlockers = newPhase == PhaseType.COMBAT_DECLARE_BLOCKERS;
-            handleCombat(game, newPlayerTurn, newPlayerTurn.getSingleOpponent(), toDeclareBlockers);
+            if (newPlayerTurn != null) {
+                handleCombat(game, newPlayerTurn, newPlayerTurn.getSingleOpponent(), toDeclareBlockers);
+            }
         }
 
         game.getStack().setResolving(false);
@@ -891,7 +893,9 @@ public abstract class GameState {
             }
         }
 
-        sa.setActivatingPlayer(c.getController());
+        if (sa != null) {
+            sa.setActivatingPlayer(c.getController());
+        }
         handleScriptedTargetingForSA(game, sa, tgtID);
 
         if (putOnStack) {

forge-ai/src/main/java/forge/ai/PlayerControllerAi.java

@@ -733,6 +733,7 @@ public class PlayerControllerAi extends PlayerController {
                                     return true;
                                 }
                             }
+                            break;
                         case "BetterTgtThanRemembered":
                             if (source.getRememberedCount() > 0) {
                                 Card rem = (Card) source.getFirstRemembered();
@@ -746,6 +747,7 @@ public class PlayerControllerAi extends PlayerController {
                                 }
                                 return false;
                             }
+                            break;
                         default:
                             break;
                     }

forge-ai/src/main/java/forge/ai/SpecialCardAi.java

@@ -172,7 +172,7 @@ public class SpecialCardAi {
                 }
             }
 
-            return best.getName();
+            return best != null ? best.getName() : "";
         }
     }
 
@@ -1231,7 +1231,7 @@ public class SpecialCardAi {
             // no options with smaller CMC, so discard the one that is harder to cast for the one that is
             // easier to cast right now, but only if the best card in the library is at least CMC 3
             // (probably not worth it to grab low mana cost cards this way)
-            if (maxCMC != null && maxCMC.getCMC() < bestInLib.getCMC() && bestInLib.getCMC() >= 3) {
+            if (maxCMC != null && bestInLib != null && maxCMC.getCMC() < bestInLib.getCMC() && bestInLib.getCMC() >= 3) {
                 return maxCMC;
             }
             // We appear to be playing Reanimator (or we have a reanimator card in hand already), so it's

forge-game/src/main/java/forge/game/GameActionUtil.java

@@ -311,6 +311,7 @@ public final class GameActionUtil {
                 break;
             case Flash:
                 result.getRestrictions().setInstantSpeed(true);
+                break;
             default:
                 break;
             }

forge-gui-desktop/src/main/java/forge/toolbox/SaveOpenDialog.java

@@ -111,7 +111,7 @@ public class SaveOpenDialog extends JPanel {
             RetFile = fc.getSelectedFile();
 
             /* Adds extension if it is known and not given */
-            if (type != null & !(RetFile.getAbsolutePath().endsWith(type.TypeExtension))) {
+            if (type != null && !(RetFile.getAbsolutePath().endsWith(type.TypeExtension))) {
                 RetFile = new File(RetFile.getAbsolutePath() + "." + type.TypeExtension);
             }
 

forge-gui/src/main/java/forge/download/GuiDownloadZipService.java

@@ -214,13 +214,13 @@ public class GuiDownloadZipService extends GuiDownloadService {
     protected void copyInputStream(final InputStream in, final String outPath) throws IOException {
         final byte[] buffer = new byte[1024];
         int len;
-        final BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(outPath));
 
-        while((len = in.read(buffer)) >= 0) {
+        try (BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(outPath))) {
-            out.write(buffer, 0, len);
+            while ((len = in.read(buffer)) >= 0) {
+                out.write(buffer, 0, len);
+            }
         }
 
         in.close();
-        out.close();
     }
 }

forge-gui/src/main/java/forge/net/server/FServerManager.java

@@ -218,28 +218,26 @@ public final class FServerManager {
     //  https://stackoverflow.com/a/34873630
     //  https://stackoverflow.com/a/901943
     private String getRoutableAddress(boolean preferIpv4, boolean preferIPv6) throws SocketException, UnknownHostException {
-        DatagramSocket s = new DatagramSocket();
+        try (DatagramSocket s = new DatagramSocket()) {
-        s.connect(InetAddress.getByAddress(this.externalAddress), 0);
+            s.connect(InetAddress.getByAddress(this.externalAddress), 0);
-        NetworkInterface n = NetworkInterface.getByInetAddress(s.getLocalAddress());
+            NetworkInterface n = NetworkInterface.getByInetAddress(s.getLocalAddress());
-        Enumeration<InetAddress> en = n.getInetAddresses();
+            Enumeration<InetAddress> en = n.getInetAddresses();
-        while (en.hasMoreElements()) {
+            while (en.hasMoreElements()) {
-            InetAddress addr = (InetAddress) en.nextElement();
+                InetAddress addr = (InetAddress) en.nextElement();
-            if (addr instanceof Inet4Address) {
+                if (addr instanceof Inet4Address) {
-                if (preferIPv6) {
+                    if (preferIPv6) {
-                    continue;
+                        continue;
+                    }
+                    return addr.getHostAddress();
                 }
-                s.close();
+                if (addr instanceof Inet6Address) {
-                return addr.getHostAddress();
+                    if (preferIpv4) {
-            }
+                        continue;
-            if (addr instanceof Inet6Address) {
+                    }
-                if (preferIpv4) {
+                    return addr.getHostAddress();
-                    continue;
                 }
-                s.close();
-                return addr.getHostAddress();
             }
         }
-        s.close();
         return null;
     }
 

forge-gui/src/main/java/forge/player/PlayerControllerHuman.java

@@ -2040,9 +2040,9 @@ public class PlayerControllerHuman extends PlayerController implements IGameCont
                 final File f = GuiBase.getInterface().getSaveFile(new File(ForgeConstants.USER_GAMES_DIR, "state.txt"));
                 if (f != null
                         && (!f.exists() || getGui().showConfirmDialog("Overwrite existing file?", "File exists!"))) {
-                    final BufferedWriter bw = new BufferedWriter(new FileWriter(f));
+                    try (BufferedWriter bw = new BufferedWriter(new FileWriter(f))) {
-                    bw.write(state.toString());
+                        bw.write(state.toString());
-                    bw.close();
+                    }
                 }
             } catch (final Exception e) {
                 String err = e.getClass().getName();