Spring Boot中动态读取和持久化外部JSON文件教程

json.file.path=/path/to/your/external/json/file.json
# 例如：json.file.path=./data/file.json (相对于应用启动目录)
# 或：json.file.path=/opt/app/data/file.json (绝对路径)

// package com.example.demo.model;
// import lombok.Data;
// @Data
// public class Master {
//    // ... 你的Master实体字段
//    private Long id;
//    private String name;
//    // ...
// }

package com.example.demo.Repository;

import com.example.demo.model.Master;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface MasterRepository extends CrudRepository<Master, Long> {
}

package com.example.demo.Services;

import com.example.demo.Repository.MasterRepository;
import com.example.demo.model.Master;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional; // 导入事务注解

import java.util.List;

@Service
public class MasterService {
    private final MasterRepository masterRepository; // 使用final修饰，强调不可变性

    // 构造器注入
    public MasterService(MasterRepository masterRepository) {
        this.masterRepository = masterRepository;
    }

    public Iterable<Master> list() {
        return masterRepository.findAll();
    }

    @Transactional // 确保保存操作在事务中执行
    public Master save(Master master) {
        return masterRepository.save(master);
    }

    @Transactional // 确保批量保存操作在事务中执行
    public Iterable<Master> save(List<Master> masters) {
        return masterRepository.saveAll(masters);
    }
}

package com.example.demo;

import com.example.demo.Services.MasterService;
import com.example.demo.model.Master;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.Data;
import org.springframework.beans.factory.annotation.Value; // 导入Value注解
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files; // 导入Files工具类
import java.nio.file.Path; // 导入Path类
import java.nio.file.Paths; // 导入Paths工具类
import java.util.List;

// 假设MasterList不再需要，直接读取List<Master>
// @Data
// class MasterList {
//    List<Master> masterList;
// }

@SpringBootApplication
@EnableScheduling // 启用定时任务
@EnableTransactionManagement // 启用事务管理
public class ReadAndWriteJsonApplication {

    private final MasterService masterService; // 使用final修饰

    @Value("${json.file.path}") // 注入配置文件中的JSON文件路径
    private String jsonFilePath;

    // 构造器注入MasterService
    public ReadAndWriteJsonApplication(MasterService masterService) {
        this.masterService = masterService;
    }

    public static void main(String[] args) {
        SpringApplication.run(ReadAndWriteJsonApplication.class, args);
        // 移除TimerTaskUtil的调用，因为我们使用Spring的@Scheduled
    }

    @Scheduled(fixedRate = 90000) // 每90秒执行一次
    public void readFileAndSaveToDatabase() {
        ObjectMapper mapper = new ObjectMapper();
        TypeReference<List<Master>> typeReference = new TypeReference<List<Master>>() {};

        Path filePath = Paths.get(jsonFilePath); // 根据配置路径创建Path对象

        try (InputStream inputStream = Files.newInputStream(filePath)) { // 使用Files.newInputStream获取实时文件流
            List<Master> masters = mapper.readValue(inputStream, typeReference);
            System.out.println("成功读取到数据: " + masters);

            // 批量保存到数据库，Service层已添加@Transactional
            masterService.save(masters);
            System.out.println("数据已成功保存到数据库。");

        } catch (IOException e) {
            System.err.println("读取或保存JSON文件时发生错误: " + e.getMessage());
            // 生产环境中应使用日志框架记录错误，如SLF4J + Logback
        } catch (Exception e) {
            System.err.println("处理数据时发生未知错误: " + e.getMessage());
        }
    }
}