Java中的静态方法-最佳做法？

Question

I'm wondering, that using static method, like in example below, is good or bad behavior. Let me know, what you think :)

class SomeClass{

    static String appendString(String text){
        return text + "a";
    }
}

This is pure example, but I'm using this kind of method a lot. Always I'm passing all required params, never use any content in method class.

Answer 1

In general as far as the result of the static method call, does not have any side effects, there is no issues with this approach.

Although, there is one gotcha that you have to have in mind. Unit testing of classes calling your static methods. If you use actual object you can use test double and simulate (mock) behavior, which is not possible when referencing static methods.

Answer 2

I like to use static methods for functions that are re-used a lot in my projects.

So, in my opinion, if this method is going to be used in a lot of different classes, then make it static.

Answer 3

It depends on the content of your method. Based on your example, I would say using the static identifier for the appendString method is valid. In general any method that does not require instance members of objects to be constructed yet can be static. If you are just doing manipulation on some value/data passed in (eg, converting degrees to radians) than that's perfectly ok.