Add in checks for potential NPEs. Fixes BUKKIT-1706 and BUKKIT-1590.

src/main/java/org/bukkit/craftbukkit/CraftWorld.java

@@ -443,6 +443,8 @@ public class CraftWorld implements World {
         // Forces the client to update to the new time immediately
         for (Player p : getPlayers()) {
             CraftPlayer cp = (CraftPlayer) p;
+            if (cp.getHandle().netServerHandler == null) continue;
+
             cp.getHandle().netServerHandler.sendPacket(new Packet4UpdateTime(cp.getHandle().getPlayerTime()));
         }
     }
@@ -767,6 +769,8 @@ public class CraftWorld implements World {
         radius *= radius;
 
         for (Player player : getPlayers()) {
+            if (((CraftPlayer) player).getHandle().netServerHandler == null) continue;
+
             distance = (int) player.getLocation().distanceSquared(location);
             if (distance <= radius) {
                 ((CraftPlayer) player).getHandle().netServerHandler.sendPacket(packet);

src/main/java/org/bukkit/craftbukkit/entity/CraftHumanEntity.java

@@ -221,6 +221,7 @@ public class CraftHumanEntity extends CraftLivingEntity implements HumanEntity {
     }
 
     private void openCustomInventory(Inventory inventory, EntityPlayer player, int windowType) {
+        if (player.netServerHandler == null) return;
         Container container = new CraftContainer(inventory, this, player.nextContainerCounter());
 
         container = CraftEventFactory.callInventoryOpenEvent(player, container);
@@ -270,6 +271,7 @@ public class CraftHumanEntity extends CraftLivingEntity implements HumanEntity {
 
     public void openInventory(InventoryView inventory) {
         if (!(getHandle() instanceof EntityPlayer)) return; // TODO: NPC support?
+        if (((EntityPlayer) getHandle()).netServerHandler == null) return;
         if (getHandle().activeContainer != getHandle().defaultContainer) {
             // fire INVENTORY_CLOSE if one already open
             ((EntityPlayer)getHandle()).netServerHandler.handleContainerClose(new Packet101CloseWindow(getHandle().activeContainer.windowId));

src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java

@@ -240,6 +240,7 @@ public class CraftLivingEntity extends CraftEntity implements LivingEntity {
         getHandle().effects.remove(type.getId());
         getHandle().e = true; // Should be called updateEffects
         if (getHandle() instanceof EntityPlayer) {
+            if (((EntityPlayer) getHandle()).netServerHandler == null) return;
             ((EntityPlayer) getHandle()).netServerHandler.sendPacket(new Packet42RemoveMobEffect(getHandle().id, new MobEffect(type.getId(), 0, 0)));
         }
     }

src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java

@@ -178,6 +178,7 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         Packet201PlayerInfo packet = new Packet201PlayerInfo(name, true, getHandle().ping);
         for (int i = 0; i < server.getHandle().players.size(); ++i) {
             EntityPlayer entityplayer = (EntityPlayer) server.getHandle().players.get(i);
+            if (entityplayer.netServerHandler == null) continue;
 
             if (entityplayer.getBukkitEntity().canSee(this)) {
                 entityplayer.netServerHandler.sendPacket(oldpacket);
@@ -587,6 +588,7 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
 
     public void hidePlayer(Player player) {
         Validate.notNull(player, "hidden player cannot be null");
+        if (getHandle().netServerHandler == null) return;
         if (equals(player)) return;
         if (hiddenPlayers.containsKey(player.getName())) return;
         hiddenPlayers.put(player.getName(), player);
@@ -605,6 +607,7 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
 
     public void showPlayer(Player player) {
         Validate.notNull(player, "shown player cannot be null");
+        if (getHandle().netServerHandler == null) return;
         if (equals(player)) return;
         if (!hiddenPlayers.containsKey(player.getName())) return;
         hiddenPlayers.remove(player.getName());
@@ -732,6 +735,7 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
 
     public void sendPluginMessage(Plugin source, String channel, byte[] message) {
         StandardMessenger.validatePluginMessage(server.getMessenger(), source, channel, message);
+        if (getHandle().netServerHandler == null) return;
 
         if (channels.contains(channel)) {
             Packet250CustomPayload packet = new Packet250CustomPayload();
@@ -755,6 +759,7 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
     }
 
     public void sendSupportedChannels() {
+        if (getHandle().netServerHandler == null) return;
         Set<String> listening = server.getMessenger().getIncomingChannels();
 
         if (!listening.isEmpty()) {