This rule states that a class should be declared as static if it only contains static members. Declaring a class as static indicates that it cannot be instantiated or extended and that all its members are static. This provides a clear signal to other developers that this class is not meant to be used as an object.
// all attributes are static, the class should be staticpublicclassFoo{privatestaticstring_f;publicstaticvoidBar(){}}publicclassFooBar{privatestaticreadonlyIList<MyObject>LargeCollection;FooBar(){stringjson=System.IO.File.ReadAllText(TestFixtureBase.ResolvePath("large.json"));LargeCollection=JsonConvert.DeserializeObject<IList<RootObject>>(json);}publicstaticvoidPlop(){}}