error on making player chat

so my code:

Code:java

public boolean onCommand(CommandSender sender, Command cmd, String alias, String[] args) {
 
    //if not player, return
    if(!(sender instanceof Player)){
        return true;
    }
 
    //get player
    Player player = (Player) sender;
 
    //permission check if player is trying to use admin or mod chat
    if((cmd.getName().equalsIgnoreCase("a") && !player.hasPermission("brierieutil.admin")) || (cmd.getName().equalsIgnoreCase("m") && !player.hasPermission("brierieutil.mod"))){
        player.sendMessage(ChatColor.RED + "You do not have permission to use this command.");
        return true;
    }
 
    //get the player's current channel
    ChannelType channel = ChatChannelHandler.getChannel(player.getUniqueId());
 
    //set the channel based on command used
    switch(cmd.getName()){
        case "a":
            ChatChannelHandler.setChannel(player.getUniqueId(), ChannelType.ADMIN);
            break;
        case "g":
            ChatChannelHandler.setChannel(player.getUniqueId(), ChannelType.GLOBAL);
            break;
        case "l":
            ChatChannelHandler.setChannel(player.getUniqueId(), ChannelType.LOCAL);
            break;
        case "m":
            ChatChannelHandler.setChannel(player.getUniqueId(), ChannelType.MOD);
            break;
        case "nc":
            ChatChannelHandler.setChannel(player.getUniqueId(), ChannelType.NATION);
            break;
        case "tc":
            ChatChannelHandler.setChannel(player.getUniqueId(), ChannelType.TOWN);
            break;
    }
 
    //get section containing worldgroups
    ConfigurationSection path = ChatConfig.get("worldGroups");
    String worldgroup = "";
 
    //find world group
    for(String group: path.getKeys(false)){
        if(path.getStringList(group + ".worlds").contains(player.getWorld().getName())){
            worldgroup = group;
        }
    }
 
    //get the group section from the config
    path = path.getConfigurationSection(worldgroup);
 
    //check to see if chat is enabled for worldgroup
    boolean flag = false;
    String chats[] = path.getString("chats").split(",");
    for(String s: chats){
        if(s.equalsIgnoreCase(ChatChannelHandler.getChannel(player.getUniqueId()).toString())){
            flag = true;
        }
    }
 
    if(flag == false){
        player.sendMessage(ChatColor.DARK_RED + "That chat is not enabled for this world.");
        return true;
    }
 
    //if there are arguments, send the message and change channel back to what it was before
    if(args.length != 0){
        String message = "";
        for(String s: args){
            message += s + " ";
        }
        player.chat(message);
        ChatChannelHandler.setChannel(player.getUniqueId(), channel);
        return true;
    }
    //if already in specified channel switch to local
    else if(ChatChannelHandler.getChannel(player.getUniqueId()).equals(channel)){
        ChatChannelHandler.setChannel(player.getUniqueId(), ChannelType.LOCAL);
        player.sendMessage(ChatColor.DARK_GREEN + "Switching to LOCAL chat.");
        return true;
    //switch to chat specified
    } else{
        player.sendMessage(ChatColor.DARK_GREEN + "Switching to " + ChatChannelHandler.getChannel(player.getUniqueId()).toString() + " chat.");
        return true;
    }
}

on the line that says "player.chat(message)" sometimes this error will be thrown:

Code:

org.bukkit.command.CommandException: Unhandled exception executing command 'a' in plugin BrierieUtil v0.2
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[craftbukkit.jar:git-Spigot-1570]
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:181) ~[craftbukkit.jar:git-Spigot-1570]
    at org.bukkit.craftbukkit.v1_7_R4.CraftServer.dispatchCommand(CraftServer.java:767) ~[craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.PlayerConnection.handleCommand(PlayerConnection.java:1017) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.PlayerConnection.a(PlayerConnection.java:847) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.PacketPlayInChat.a(PacketPlayInChat.java:28) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.PacketPlayInChat.handle(PacketPlayInChat.java:65) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.NetworkManager.a(NetworkManager.java:184) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.ServerConnection.c(ServerConnection.java:81) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.MinecraftServer.v(MinecraftServer.java:731) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.DedicatedServer.v(DedicatedServer.java:289) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.MinecraftServer.u(MinecraftServer.java:584) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java:490) [craftbukkit.jar:git-Spigot-1570]
    at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:628) [craftbukkit.jar:git-Spigot-1570]
Caused by: java.lang.RuntimeException: Exception processing chat event
    at net.minecraft.server.v1_7_R4.PlayerConnection.chat(PlayerConnection.java:977) ~[craftbukkit.jar:git-Spigot-1570]
    at org.bukkit.craftbukkit.v1_7_R4.entity.CraftPlayer.chat(CraftPlayer.java:264) ~[craftbukkit.jar:git-Spigot-1570]
    at backcab.BrierieUtil.Commands.ChatCommand.onCommand(ChatCommand.java:100) ~[?:?]
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[craftbukkit.jar:git-Spigot-1570]
    ... 13 more

(note that line 100 is the line "player.chat(message)")

I can't figure out why this error is occurring. It is somehow causing users to hit this error, and causing them to no longer be able to send chat of any kind.

My channels (for this chat plugin if you couldn't tell what it was), and their handlers all function properly with no issues as long as the command is issued without a message behind it.

 

Seek support where you acquired your server mod.