JDA Bot异常

Question

为Discord创建Java机器人时遇到问题。我决定为此命令从服务器踢出玩家。但是我遇到了困难。

这是一个代码：

package com.company;

import net.dv8tion.jda.api.EmbedBuilder;
import net.dv8tion.jda.api.Permission;
import net.dv8tion.jda.api.entities.Member;
import net.dv8tion.jda.api.events.message.guild.GuildMessageReceivedEvent;
import net.dv8tion.jda.api.hooks.ListenerAdapter;

import java.util.List;
import java.util.Objects;

public class KickComm extends ListenerAdapter {

    public void onGuildMessageReceived(GuildMessageReceivedEvent event) {
        String[] args = event.getMessage().getContentRaw().split("\\s+");

        List<Member> mentionedMembers = event.getMessage().getMentionedMembers();
        Member target = mentionedMembers.get(0);

        if(args[0].equalsIgnoreCase(Main.prefix + "kick"))
        {
            if (args.length < 2) {                                                                  //TODO NOT WORK

                EmbedBuilder NoUser = new EmbedBuilder();
                NoUser.setColor(0xff3923);
                NoUser.setTitle("\uD83D\uDD34You need to add a <@username> and <reason>");
                NoUser.setFooter("Usage: " + Main.prefix + "kick <@username> <reason>.",
                        Objects.requireNonNull(event.getMember()).getUser().getAvatarUrl());

                event.getChannel().sendMessage(NoUser.build()).queue();

                NoUser.clear();
            }

            else if (args.length < 3) {                                                                //WORK

                EmbedBuilder NoReason = new EmbedBuilder();
                NoReason.setColor(0xff3923);
                NoReason.setTitle("\uD83D\uDD34You need to add a <reason>.");
                NoReason.setFooter("Usage: " + Main.prefix + "kick <@username> <reason>.",
                        Objects.requireNonNull(event.getMember()).getUser().getAvatarUrl());

                event.getChannel().sendMessage(NoReason.build()).queue();

                NoReason.clear();
            }

            else if(!Objects.requireNonNull(event.getMember()).hasPermission(Permission.KICK_MEMBERS)  //WORK
                &&
                     !event.getMember().canInteract(target)) {

                EmbedBuilder NoPermission = new EmbedBuilder();
                NoPermission.setColor(0xff3923);
                NoPermission.setTitle("\uD83D\uDD34You don't have permission to use this command.");
                NoPermission.setFooter("Usage: " + Main.prefix + "kick <@username> <reason>.",
                        Objects.requireNonNull(event.getMember()).getUser().getAvatarUrl());

                event.getChannel().sendMessage(NoPermission.build()).queue();

                NoPermission.clear();
            }

            else if(mentionedMembers.isEmpty()) {                                                       //TODO NOT WORK 

                EmbedBuilder NoMember = new EmbedBuilder();
                NoMember.setColor(0xff3923);
                NoMember.setTitle("\uD83D\uDD34I don't see member with this nickname.");
                NoMember.setFooter("Usage: " + Main.prefix + "kick <@username> <reason>.",
                        Objects.requireNonNull(event.getMember()).getUser().getAvatarUrl());

                event.getChannel().sendMessage(NoMember.build()).queue();

                NoMember.clear();
            }
        }
    }
}

两行提示：

if (args.length < 2) {

和

else if(mentionedMembers.isEmpty()) {

最重要的是，我不明白为什么第1行不起作用。当我在不和谐中编写！kick命令时，控制台显示错误：

java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0

我不知道为什么args长度为0，这很奇怪。我试图将“ if-else-if”改为“ if”，但是它不起作用。我真的想继续创建该命令，但是我不知道该怎么办。

P.S .:并非全部代码，因为该错误导致我无法进一步前进。对不起，我的Google翻译器英文非常感谢

Answer 1

此行引起异常：

Member target = mentionedMembers.get(0);

您的问题是，并非每条消息都可能提及一个成员。请记住，您还会收到自己的消息。如果漫游器仅发送嵌入内容，则内容将为空。

如果内容仅是空白，则split("\\s+")将返回一个空数组。这将在此行上产生ArrayIndexOutOfBoundsException：

if(args[0].equalsIgnoreCase(Main.prefix + "kick"))

在尝试访问各自的元素之前，我建议检查mentionedMembers的长度并检查args的长度。