如果玩家键入 /launch <notaninteger> 或 /launch String，我如何让我的代码 return 向玩家发送 "Invalid number" 消息

Question


import org.bukkit.ChatColor;
import org.bukkit.command.Command;
import org.bukkit.command.CommandExecutor;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;


public class launch implements CommandExecutor {
    @Override
    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
        if (label.equalsIgnoreCase("launch") || label.equalsIgnoreCase("l")) {
            if (!(sender instanceof Player)) {
                sender.sendMessage(ChatColor.translateAlternateColorCodes('&', "&7[&dHi&bMessage&7]  &4Invalid Entity"));
                return true;
            }
            Player player = (Player) sender;
            //Does /launch or /launch <amplifier>
            if (args.length == 0) {
                player.sendMessage(ChatColor.translateAlternateColorCodes('&', "&7[&dHi&bMessage&7]  &2Launching in &a3"));
                try {
                    Thread.sleep(1000);
                    player.sendMessage(ChatColor.translateAlternateColorCodes('&', "&7[&dHi&bMessage&7]  &2Launching in &62"));
                } catch (InterruptedException e) {
                    System.err.println(e.getMessage());
                }
                try {
                    Thread.sleep(1000);
                    player.sendMessage(ChatColor.translateAlternateColorCodes('&', "&7[&dHi&bMessage&7]  &2Launching in &c1"));
                } catch (InterruptedException e) {
                    System.err.println(e.getMessage());
                }
                player.setVelocity(player.getLocation().getDirection().multiply(2).setY(1.5));
                return true;
            }


            //Launch but with args
            player.sendMessage(ChatColor.translateAlternateColorCodes('&', "&7[&dHi&bMessage&7]  &2Launching in &a3"));
            try {
                Thread.sleep(1000);
                player.sendMessage(ChatColor.translateAlternateColorCodes('&', "&7[&dHi&bMessage&7]  &2Launching in &62"));
            } catch (InterruptedException e) {
                System.err.println(e.getMessage());
            }
            try {
                Thread.sleep(1000);
                player.sendMessage(ChatColor.translateAlternateColorCodes('&', "&7[&dHi&bMessage&7]  &2Launching in &c1"));
            } catch (InterruptedException e) {
                System.err.println(e.getMessage());
            }
            player.setVelocity(player.getLocation().getDirection().multiply(Integer.parseInt(args[0])).setY(1.5));
            player.setHealth(20.0);

            return true;
        }
    return false;
    }}

也许我可以添加 if 语句或带有 NonIntegerException 的 catch？请耐心等待，因为我是一名新的年轻开发人员，我已经看到如果有人不知道如何正确格式化问题，人们会得到 upset/angry。再一次，如标题所示，我的问题是：如果玩家键入 /launch 或 /launch String

，我如何让我的代码 return 向玩家发送“无效数字”消息

Answer 1

在“//Launch but with args”之后，您必须检查 args[0] 是否为整数。我建议为此定义一个方法：

public boolean isInteger(String arg) {
        try {
            Integer.parseInt(arg);
        } catch (NumberFormatException e) {
            return false;
        }
        return true;
}

然后在开始倒计时之前，您可以添加如下内容：

if (!isInteger(args[0])) {
    player.sendMessage("Invalid number");
    return true;
}

如果玩家键入 /launch <notaninteger> 或 /launch String，我如何让我的代码 return 向玩家发送 "Invalid number" 消息

How can I make my code return a "Invalid number" message to a player if they type /launch <notaninteger> or /launch String

java

plugins

minecraft