We only need the name here, avoids NPE issues in /party create.

Fixes #655

src/main/java/com/gmail/nossr50/party/PartyManager.java

@@ -21,15 +21,15 @@ public final class PartyManager {
 
     private PartyManager() {}
 
-    public static boolean changeOrJoinParty(McMMOPlayer mcMMOPlayer, Player player, Party oldParty, Party newParty) {
+    public static boolean changeOrJoinParty(McMMOPlayer mcMMOPlayer, Player player, Party oldParty, String newPartyName) {
         if (mcMMOPlayer.inParty()) {
-            if (!handlePartyChangeEvent(player, oldParty.getName(), newParty.getName(), EventReason.CHANGED_PARTIES)) {
+            if (!handlePartyChangeEvent(player, oldParty.getName(), newPartyName, EventReason.CHANGED_PARTIES)) {
                 return false;
             }
 
             removeFromParty(player.getName(), oldParty);
         }
-        else if (!handlePartyChangeEvent(player, null, newParty.getName(), EventReason.JOINED_PARTY)) {
+        else if (!handlePartyChangeEvent(player, null, newPartyName, EventReason.JOINED_PARTY)) {
             return false;
         }
 

src/main/java/com/gmail/nossr50/party/commands/PartyAcceptCommand.java

@@ -34,7 +34,7 @@ public class PartyAcceptCommand implements CommandExecutor {
 
 
             // Changing parties
-            if (!PartyManager.changeOrJoinParty(mcMMOPlayer, player, mcMMOPlayer.getParty(), mcMMOPlayer.getPartyInvite())) {
+            if (!PartyManager.changeOrJoinParty(mcMMOPlayer, player, mcMMOPlayer.getParty(), mcMMOPlayer.getPartyInvite().getName())) {
                 return true;
             }
 

src/main/java/com/gmail/nossr50/party/commands/PartyCreateCommand.java

@@ -38,7 +38,7 @@ public class PartyCreateCommand implements CommandExecutor {
             mcMMOPlayer = Users.getPlayer(player);
 
             // Changing parties
-            if (!PartyManager.changeOrJoinParty(mcMMOPlayer, player, mcMMOPlayer.getParty(), newParty)) {
+            if (!PartyManager.changeOrJoinParty(mcMMOPlayer, player, mcMMOPlayer.getParty(), args[1])) {
                 return true;
             }
 

src/main/java/com/gmail/nossr50/party/commands/PartyJoinCommand.java

@@ -45,7 +45,7 @@ public class PartyJoinCommand implements CommandExecutor {
             }
 
             // Changing parties
-            if (!PartyManager.changeOrJoinParty(mcMMOPlayer, player, playerParty, targetParty)) {
+            if (!PartyManager.changeOrJoinParty(mcMMOPlayer, player, playerParty, targetParty.getName())) {
                 return true;
             }