最近，我做了一个控制台应用程序，如您现在所需。我通过实施 CommandLineRunner 接口。当springboot启动应用程序时，它将调用 run(String... args) 方法 CommandLineRunner 接口。因此，您可以在此实现类（例如apprunner）中自动连接（或使用构造函数注入）spring数据存储库并调用数据库操作。
我使用了mongodb和一些缓存操作，而不是mysql数据库。
例子：
apprunner.java文件

package com.cache.caching;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.CommandLineRunner;
import org.springframework.stereotype.Component;

@Component
public class AppRunner implements CommandLineRunner {

    Logger logger = LoggerFactory.getLogger(AppRunner.class);

    BookRepository bookRepository;

    public AppRunner(BookRepository bookRepository) {
        this.bookRepository = bookRepository;
    }

    @Override
    public void run(String... args) throws Exception {
        logger.info("articles fetching..."+bookRepository.getArticles());
        logger.info("articles fetching..."+bookRepository.getArticles());
        logger.info("articles fetching..."+bookRepository.getArticles());
        logger.info("articles fetching..."+bookRepository.getArticles());
    }
}

bookrepository.java文件

package com.cache.caching;

import java.net.UnknownHostException;
import java.util.List;

public interface BookRepository {
    List<Article> getArticles() throws UnknownHostException;
}

bookrepositoryimpl.java文件

package com.cache.caching;

import com.mongodb.*;
import org.bson.codecs.pojo.annotations.BsonId;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.data.mongodb.MongoCollectionUtils;
import org.springframework.stereotype.Component;

import java.util.ArrayList;
import java.util.List;
import java.util.function.Consumer;

@Component
public class BookRepositoryImpl implements BookRepository{

    @Override
    @Cacheable("articles")
    public List<Article> getArticles() throws UnknownHostException {

        MongoClient mongoClient
                = new MongoClient(new MongoClientURI("mongodb://localhost:27017"));
        DB db = mongoClient.getDB("Mart");
        DBCollection collection =  db.getCollection("articles");
        DBCursor cursor = collection.find();
        List<Article> list= new ArrayList<>();
        while (cursor.hasNext()) {
           Article article = new Article();
           DBObject dbObject = cursor.next();
           article.setId((Double) dbObject.get("_id"));
           article.setSubject((String) dbObject.get("subject"));
           list.add(article);
        }
        return list;
    }

}

在您的例子中，您可以在application.yml/application.properties文件中提供mysql数据库连接的详细信息。
cachingaapplication.java-应用程序从这里开始，如下所示 SpringApplication.run(CachingApplication.class, args); 调用 run(String... args) 方法 CommandLineRunner 接口。

package com.cache.caching;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.EnableCaching;

@SpringBootApplication
@EnableCaching
public class CachingApplication {

    public static void main(String[] args) {
        SpringApplication.run(CachingApplication.class, args);
    }

}

示例：这里是完整示例示例