HarmonyOS 单例模式拿不到类的对象

export class GlobalContext {  
    private constructor() {  
    }  
  
    private static instance: GlobalContext;  
    private _objects = new Map<string, Object>();  
  
    public static getContext(): GlobalContext {  
        if (!GlobalContext.instance) {  
            GlobalContext.instance = new GlobalContext();  
        }  
        return GlobalContext.instance;  
    }  
  
    getObject(value: string): Object | undefined {  
        return this._objects.get(value);  
    }  
  
    setObject(key: string, objectClass: Object): void {  
        this._objects.set(key, objectClass);  
    }  
}