like so
package com.example.accessingdatajpa;
import org.aspectj.weaver.ast.And;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;

import java.util.Optional;

@SpringBootApplication
public class AccessingDataJpaApplication {

    private static final Logger log = LoggerFactory.getLogger(AccessingDataJpaApplication.class);

    public static void main(String[] args) {
        SpringApplication.run(AccessingDataJpaApplication.class);
    }
     @Bean
     public CommandLineRunner demo(MedicineRepository repository){
        return (args)->{
            //BusinessLogic
            repository.save(new Medicine(1,"Pandol","Paracetamo , Maize starch","Al-Hikma","Safe for children",
                                "Safe for pregenent"," 250g for Driving" ));
            repository.save(new Medicine(2,"Aspirin","Paracetamo , Maize starch","Al-Hikma"," Not Safe for children",
                    "Safe for pregenent"," 250g for Driving" ));
            //Fetch all Medicine
            log.info("Medicine found with findAll():");
            log.info("-------------------------------");
            for (Medicine medicine : repository.findAll()) {
                log.info(medicine.toString());
            }
            log.info("");
             `like so fetch an individual customer by ID `
            Optional<Medicine> medicine = repository.findById(1L);
            log.info("Medicine found with findById(1L):");
            log.info("--------------------------------");
            log.info(medicine.toString());
            log.info("");
            // fetch customers by last name
            log.info("Medicine found with findByname('Aspirin'):");
            log.info("--------------------------------------------");
            repository.findByMedName("Aspirin").forEach(aspirin -> {
                log.info(aspirin.toString());
            });

            log.info("");
        };
     }

我为medicine类编写了代码，没有错误，但是在运行代码时，它运行了，但是结果显示在customer表中（我删除了main上customer的代码，并将customer表作为注解，但是结果仍然像屏幕上显示的那样）