springboot 啟動時加載數據庫數據到本地Map

 

InitDataConfig.java

import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.lang.Dict;
import com.ebc.db.MyDb;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.context.ServletContextAware;

import javax.servlet.ServletContext;
import java.math.BigDecimal;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

@Configuration
@Slf4j
public class InitDataConfig implements InitializingBean, ServletContextAware {
    /**
     * 全局每月應上小時數
     */
    public static Map<String, BigDecimal> MONTH_SHOULD_HOURS_MAP = new ConcurrentHashMap<String, BigDecimal>();
    /**
     * 月份列表，用於頁面供用戶選擇
     */
    public static List<String> MONTH_LIST = CollUtil.newArrayList();

    @Autowired
    private MyDb myDb;

    @Override
    public void setServletContext(ServletContext servletContext) {
        List<Dict> dictList = null;
        try {
            dictList = myDb.selectWorkinghoursAllList();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        if (dictList != null && dictList.size()>0) {
            Dict d = null;
            for (int i = 0; i < dictList.size(); i++) {
                d = dictList.get(i);
                MONTH_SHOULD_HOURS_MAP.put(d.getStr("month_date"),d.getBigDecimal("month_should_hours"));
                MONTH_LIST.add(d.getStr("month_date"));
            }
            log.info("初始化每月應上小時數到本地map完成");
        } else {
            log.error("每月應上小時數表數據是空的，請先初始化數據!");
        }
    }
    @Override
    public void afterPropertiesSet() throws Exception {
    }
}

調用：

@RequestMapping("/")
public String index(ModelMap modelMap) {
    modelMap.addAttribute("MONTH_LIST", InitDataConfig.MONTH_LIST);
    return "index";
}