You can put all of them in a single class or interface (to centralize all of your message definitions in a single location), or you can place these constants in the classes where they are used.
可以将它们放在单独的类或接口中(将所有消息定义集中到一个地点)，也可以放在使用到它们的类中。
2
In existing fault location algorithms the parameters of power transmission line are regarded as known constants, so the accuracy of fault location depends on that of the value of parameters.