     ///  :param: cls 模型类
     ///
     ///  :returns: 如果存在返回模型信息字典，否则返回 nil
-    func cacheModel(cls: AnyClass) -> Dictionary<String, AnyObject?>? {
+    func cacheModel(cls: AnyClass) -> Dictionary<String, AnyObject>? {
         return modelCahce["\(cls)"]
     }
     
     /// 模型缓冲池
-    var modelCahce = Dictionary<String, Dictionary<String, AnyObject?>>()
+    var modelCahce = Dictionary<String, Dictionary<String, AnyObject>>()
 }
 
 extension Dictionary {

    ///  获取完整模型信息
    ///
    ///  :param: cls 模型类
    func fullModelInfo(cls: AnyClass) -> Dictionary<String, AnyObject?> {
        
        if let cache = cacheModel(cls) {
            return cache

        var c: AnyClass? = cls
        
        // 属性字典
        var infoDict = Dictionary<String, AnyObject>()
        do {
            // 追加属性字典
            infoDict.merge(modelInfo(c!))
