Bukkit-EventHandler方法出错

Question

For Some reason I've been receiving an error when I do something with the @EventHandler annotation. I'm using Bukkit 1.7.9. Here's the part of my code:

@EventHandler
public void onSignChange(SignChangeEvent event, CommandSender sender, Command cmd, String commandLabel){
    Player player = event.getPlayer();
    if(player.hasPermission("CustomJoinSigns.Create")) {
        if(event.getLine(0).equalsIgnoreCase("Minigame")) {
            player.sendMessage(ChatColor.BLUE + "Please type in the minigame name:");
            player.sendMessage(ChatColor.GOLD + "1)" + ChatColor.RED + "Do " + ChatColor.YELLOW + "/cjs setminigame [Minigame]");
            player.sendMessage(ChatColor.GOLD + "2)" + ChatColor.RED + "Do " + ChatColor.YELLOW + "/cjs cancel");
            if(commandLabel.equalsIgnoreCase("cjs setminigame" + minvar));
            player.sendMessage("Test Successful");
        }
    }
}

Here's my error log:

ERROR CustomJoinSigns v1 attempted to register an invalid EventHandler method signature 
"public void me.pvpcraftnetwork.customjoinsigns.Main.onSignChange(org.bukkit.event.block.SignChangeEvent,org.bukkit.command.CommandSender,org.bukkit.command.Command,java.lang.String)"
in class me.pvpcraftnetwork.customjoinsigns.Main

Any suggestions on what I did wrong?

Answer 1

You can only have one argument in your Listener methods. It should look like this:

@EventHandler
public void onSignChange(SignChangeEvent event){
  Player player = event.getPlayer();
  if(player.hasPermission("CustomJoinSigns.Create")) {
    if(event.getLine(0).equalsIgnoreCase("Minigame")) {
        player.sendMessage(ChatColor.BLUE + "Please type in the minigame name:");
        player.sendMessage(ChatColor.GOLD + "1)" + ChatColor.RED + "Do " + ChatColor.YELLOW + "/cjs setminigame [Minigame]");
        player.sendMessage(ChatColor.GOLD + "2)" + ChatColor.RED + "Do " + ChatColor.YELLOW + "/cjs cancel");
        if(commandLabel.equalsIgnoreCase("cjs setminigame" + minvar));
        player.sendMessage("Test Successful");
    }
  }
}

The arguments CommandSender sender, Command cmd, String commandLabel are used in commands... So maybe you thought registering events was like listening for when a player runs a command?

Again, ALL @EventHandler methods can only have one argument, which is the event that you're listening for. So if you were listening for PlayerJoinEvent , you would use:

@EventHandler
public void playerJoin(PlayerJoinEvent event){
  //code here
}