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2025-08-09 a8a90fd2d5040e66cc66b3da122a7f82561ff6f6

 src/dell_targets/Dell_BaseStation.java

@@ -4,18 +4,23 @@
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;

public class Dell_BaseStation {
   static List<LocationBaseStation> baseStations;
   public static List<LocationBaseStation> baseStations;
   private static ConcurrentHashMap<String, LocationBaseStation> baseStationMap; // 以基站ID为键的映射

   public static List<LocationBaseStation> getBaseStations() throws SQLException {
      baseStations = new ArrayList<>();
      baseStationMap = new ConcurrentHashMap<>(); // 修复：初始化映射
      ResultSet rs = DBConnector.queryTableData("location_base_station");

       if (rs == null) {
              // 说明底层拿不到数据，直接抛异常或打印日志
              throw new SQLException("DBConnector.queryTableData returned null, "
                                   + "please check database connection & SQL.");
          }
      while (rs.next()) {
         LocationBaseStation baseStation = new LocationBaseStation();
         baseStation.setId((int) rs.getLong("id"));
@@ -134,4 +139,42 @@
      return baseStationMap.get(baseStationId); // O(1)复杂度直接获取
   }

   /**
     * 获取所有在线状态(onlineStatus=1)的设备（高效内存操作）
     * @return 不可修改的baseStationMap集合（避免外部修改缓存）
     */
    public static List<LocationBaseStation> getOnlineBaseStations() {
        if (baseStationMap == null || baseStationMap.isEmpty()) {
            return Collections.emptyList(); // 缓存为空时返回空集合
        }

        List<LocationBaseStation> BaseStation = new ArrayList<>();
        for (LocationBaseStation base : baseStationMap.values()) {
            if ("1".equals(base.getStatus())) { // 字符串比较避免NPE
               BaseStation.add(base);
            }
        }
        return Collections.unmodifiableList(BaseStation); // 返回不可变集合
    }
    
    /**
     * 快速获取LocationTag对象的总数（使用内存缓存提高性能）
     * @return LocationTag对象的总数
     */
    public static int getLocationBaseCount() {
        if (baseStationMap == null) {
            synchronized (LocationBaseStation.class) {
                if (baseStationMap == null) {
                    try {
                       getBaseStations(); // 初始化缓存
                    } catch (SQLException e) {
                        e.printStackTrace();
                        return 0; // 初始化失败返回0
                    }
                }
            }
        }
        return baseStationMap.size();
    }

}