Go语言视频零基础入门到精通

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错误描述：
  

1. @RequestMapping(value = "/index")
2.         public String index(@RequestParam(value = "action", required = false)
3.         String action, @RequestParam(value = "notIncludeTypeId", required = false)
4.         int notIncludeTypeId){
5.     // .... 省略代码
6. }

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       当可选参数“notIncludeTypeId”为空时，系统出现如下错误：  
  

1. Optional int parameter "notIncludeTypeId" is not present
2. but cannot be translated into a null value due to being declared as a primitive type.
3. Consider declaring it as object wrapper for the corresponding primitive type.

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错误原因：
     当可选参数“notIncludeTypeId”不存在时，Spring默认将其赋值为null，但由于notIncludeTypeId已定于为基本类型int，所以赋值失败！
解决方法：
     “Consider declaring it as object wrapper for the corresponding primitive type.”建议使用包装类型代替基本类型，如使用“Integer”代替“int”