JavaでDiscord Bot開発（Javacord）

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>hello_bot</artifactId>
    <version>1.0-SNAPSHOT</version>
    <build>
        <plugins>
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <version>3.3.0</version>
                <configuration>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                    <finalName>Hello-DiscordBot-${project.version}</finalName>
                    <appendAssemblyId>false</appendAssemblyId>
                    <archive>
                        <manifest>
                            <mainClass>discord_bot.main</mainClass>
                            <addClasspath>true</addClasspath>
                            <addExtensions>false</addExtensions>
                        </manifest>
                    </archive>
                </configuration>
                <executions>
                    <execution>
                        <id>make-assembly</id> <!-- this is used for inheritance merges -->
                        <phase>package</phase> <!-- bind to the packaging phase -->
                        <goals>
                            <goal>single</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
    <!-- Javacord -->
    <dependencies>
        <dependency>
            <groupId>org.javacord</groupId>
            <artifactId>javacord</artifactId>
            <version>3.0.6</version>
            <type>pom</type>
        </dependency>
    </dependencies>
</project>

package discord_bot;

import org.javacord.api.DiscordApi;
import org.javacord.api.DiscordApiBuilder;

public class main {
    public static void main(String args[]){
        String token = "トークン";

        DiscordApi api = new DiscordApiBuilder().setToken(token).login().join();

        api.addMessageCreateListener(event -> {
            if (event.getMessageContent().contains("こんにちは") && !event.getMessageAuthor().isBotUser()) {
                event.getChannel().sendMessage("こんにちは！"+event.getMessageAuthor().getName()+"さん！");
                System.out.println(event.getMessageAuthor().getName()+">>"+event.getMessageContent());
                System.out.println("BOT>>"+"こんにちは！"+event.getMessageAuthor().getName()+"さん！");
            }
        });
    }
}