Remove any tracked bossbars when a client switches servers.

protocol/src/main/java/net/md_5/bungee/protocol/AbstractPacketHandler.java

@@ -1,5 +1,6 @@
 package net.md_5.bungee.protocol;
 
+import net.md_5.bungee.protocol.packet.BossBar;
 import net.md_5.bungee.protocol.packet.KeepAlive;
 import net.md_5.bungee.protocol.packet.ClientSettings;
 import net.md_5.bungee.protocol.packet.ClientStatus;
@@ -143,4 +144,8 @@ public abstract class AbstractPacketHandler
     public void handle(SetCompression setCompression) throws Exception
     {
     }
+
+    public void handle(BossBar bossBar) throws Exception
+    {
+    }
 }

protocol/src/main/java/net/md_5/bungee/protocol/Protocol.java

@@ -12,6 +12,7 @@ import java.util.Arrays;
 import java.util.List;
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
+import net.md_5.bungee.protocol.packet.BossBar;
 import net.md_5.bungee.protocol.packet.Chat;
 import net.md_5.bungee.protocol.packet.ClientSettings;
 import net.md_5.bungee.protocol.packet.EncryptionRequest;
@@ -58,6 +59,7 @@ public enum Protocol
                     TO_CLIENT.registerPacket( 0x01, 0x23, Login.class );
                     TO_CLIENT.registerPacket( 0x02, 0x0F, Chat.class );
                     TO_CLIENT.registerPacket( 0x07, 0x33, Respawn.class );
+                    TO_CLIENT.registerPacket( 0x0C, 0x0C, BossBar.class, true );
                     TO_CLIENT.registerPacket( 0x38, 0x2D, PlayerListItem.class ); // PlayerInfo
                     TO_CLIENT.registerPacket( 0x3A, 0x0E, TabCompleteResponse.class );
                     TO_CLIENT.registerPacket( 0x3B, 0x3F, ScoreboardObjective.class );
@@ -165,6 +167,12 @@ public enum Protocol
         }
 
         protected final void registerPacket(int id, int newId, Class<? extends DefinedPacket> packetClass)
+        {
+            registerPacket( id, newId, packetClass, false );
+
+        }
+
+        protected final void registerPacket(int id, int newId, Class<? extends DefinedPacket> packetClass, boolean newOnly)
         {
             try
             {
@@ -176,8 +184,12 @@ public enum Protocol
             packetClasses[id] = packetClass;
             packetMap.put( packetClass, id );
 
+            if ( !newOnly )
+            {
                 packetRemap.get( ProtocolConstants.MINECRAFT_1_8 ).put( id, id );
                 packetRemapInv.get( ProtocolConstants.MINECRAFT_1_8 ).put( id, id );
+            }
+
             packetRemap.get( ProtocolConstants.MINECRAFT_1_9 ).put( newId, id );
             packetRemapInv.get( ProtocolConstants.MINECRAFT_1_9 ).put( id, newId );
         }

protocol/src/main/java/net/md_5/bungee/protocol/packet/BossBar.java

@@ -0,0 +1,110 @@
+package net.md_5.bungee.protocol.packet;
+
+import lombok.Data;
+import lombok.EqualsAndHashCode;
+import lombok.NoArgsConstructor;
+
+import io.netty.buffer.ByteBuf;
+import java.util.UUID;
+import net.md_5.bungee.protocol.AbstractPacketHandler;
+import net.md_5.bungee.protocol.DefinedPacket;
+import net.md_5.bungee.protocol.ProtocolConstants;
+
+@Data
+@NoArgsConstructor
+@EqualsAndHashCode(callSuper = false)
+public class BossBar extends DefinedPacket
+{
+
+    private UUID uuid;
+    private int action;
+    private String title;
+    private float health;
+    private int color;
+    private int division;
+    private byte flags;
+
+    public BossBar(UUID uuid, int action)
+    {
+        this.uuid = uuid;
+        this.action = action;
+    }
+
+    @Override
+    public void read(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion)
+    {
+        uuid = readUUID( buf );
+        action = readVarInt( buf );
+
+        switch ( action )
+        {
+            // Add
+            case 0:
+                title = readString( buf );
+                health = buf.readFloat();
+                color = readVarInt( buf );
+                division = readVarInt( buf );
+                flags = buf.readByte();
+                break;
+            // Health
+            case 2:
+                health = buf.readFloat();
+                break;
+            // Title
+            case 3:
+                title = readString( buf );
+                break;
+            // Style
+            case 4:
+                color = readVarInt( buf );
+                division = readVarInt( buf );
+                break;
+            // Flags
+            case 5:
+                flags = buf.readByte();
+                break;
+        }
+    }
+
+    @Override
+    public void write(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion)
+    {
+        writeUUID( uuid, buf );
+        writeVarInt( action, buf );
+
+        switch ( action )
+        {
+            // Add
+            case 0:
+                writeString( title, buf );
+                buf.writeFloat( health );
+                writeVarInt( color, buf );
+                writeVarInt( division, buf );
+                buf.writeByte( flags );
+                break;
+            // Health
+            case 2:
+                buf.writeFloat( health );
+                break;
+            // Title
+            case 3:
+                writeString( title, buf );
+                break;
+            // Style
+            case 4:
+                writeVarInt( color, buf );
+                writeVarInt( division, buf );
+                break;
+            // Flags
+            case 5:
+                buf.writeByte( flags );
+                break;
+        }
+    }
+
+    @Override
+    public void handle(AbstractPacketHandler handler) throws Exception
+    {
+        handler.handle( this );
+    }
+}

proxy/src/main/java/net/md_5/bungee/ServerConnector.java

@@ -1,13 +1,12 @@
 package net.md_5.bungee;
 
-import com.google.common.base.Objects;
 import com.google.common.base.Preconditions;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufAllocator;
 
-import java.util.List;
 import java.util.Queue;
 import java.util.Set;
+import java.util.UUID;
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
 import net.md_5.bungee.api.ChatColor;
@@ -31,7 +30,7 @@ import net.md_5.bungee.netty.HandlerBoss;
 import net.md_5.bungee.netty.PacketHandler;
 import net.md_5.bungee.protocol.DefinedPacket;
 import net.md_5.bungee.protocol.Protocol;
-import net.md_5.bungee.protocol.ProtocolConstants;
+import net.md_5.bungee.protocol.packet.BossBar;
 import net.md_5.bungee.protocol.packet.EncryptionRequest;
 import net.md_5.bungee.protocol.packet.Handshake;
 import net.md_5.bungee.protocol.packet.Kick;
@@ -218,6 +217,13 @@ public class ServerConnector extends PacketHandler
             }
             serverScoreboard.clear();
 
+            for ( UUID bossbar : user.getSentBossBars() )
+            {
+                // Send remove bossbar packet
+                user.unsafe().sendPacket( new net.md_5.bungee.protocol.packet.BossBar( bossbar, 1 ) );
+            }
+            user.getSentBossBars().clear();
+
             user.sendDimensionSwitch();
 
             user.setServerEntityId( login.getEntityId() );

proxy/src/main/java/net/md_5/bungee/UserConnection.java

@@ -11,6 +11,7 @@ import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
 import io.netty.util.internal.PlatformDependent;
 import java.net.InetSocketAddress;
+import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
@@ -124,6 +125,8 @@ public final class UserConnection implements ProxiedPlayer
     private ClientSettings settings;
     @Getter
     private final Scoreboard serverSentScoreboard = new Scoreboard();
+    @Getter
+    private final Collection<UUID> sentBossBars = new HashSet<>();
     /*========================================================================*/
     @Getter
     private String displayName;

proxy/src/main/java/net/md_5/bungee/connection/DownstreamBridge.java

@@ -29,7 +29,7 @@ import net.md_5.bungee.netty.ChannelWrapper;
 import net.md_5.bungee.netty.PacketHandler;
 import net.md_5.bungee.protocol.DefinedPacket;
 import net.md_5.bungee.protocol.PacketWrapper;
-import net.md_5.bungee.protocol.ProtocolConstants;
+import net.md_5.bungee.protocol.packet.BossBar;
 import net.md_5.bungee.protocol.packet.KeepAlive;
 import net.md_5.bungee.protocol.packet.PlayerListItem;
 import net.md_5.bungee.protocol.packet.ScoreboardObjective;
@@ -484,6 +484,22 @@ public class DownstreamBridge extends PacketHandler
         throw CancelSendSignal.INSTANCE;
     }
 
+    @Override
+    public void handle(BossBar bossBar)
+    {
+        switch ( bossBar.getAction() )
+        {
+            // Handle add bossbar
+            case 0:
+                con.getSentBossBars().add( bossBar.getUuid() );
+                break;
+            // Handle remove bossbar
+            case 1:
+                con.getSentBossBars().remove( bossBar.getUuid() );
+                break;
+        }
+    }
+
     @Override
     public String toString()
     {