static-methods

问题 I understand, thanks to this question, that the value of a static field declared in an abstract class will be the same among all subclasses. The solution in the aforementioned question is to declare a static field in each subclass, and an abstract "getter" instance method in the abstract class that must be implemented by each subclass. But I have a static method in my abstract class, and I need to refer to the static field of the subclass. I can't do this because the getter is an instance

问题 This question already has answers here : Closed 8 years ago . Possible Duplicate: When should a method be static? i am trying to make an interface class for tube/subway ticket machine. well not for real, but for a coursework in a computer science module. i dont understand when to use static methods. i dont know much about computer sciences, but main methods seem to use static. class UNInterfaceTest { public static final int NOTTING_HILL = 1; public static final int HIGH_KEN = 2; public static

问题 I believe this is purely a Resharper warning, but the reasoning behind it (explained here) makes good sense. What Greg Beech is saying is that you can call a base-class static method from a sibling class... in his example he uses: var request = (FtpWebRequest)HttpWebRequest.Create(...) ... which is misleading. So is there a design that would allow me to avoid this warning in the following classes? public abstract class BaseLog { // I omitted several other properties for clarity protected

问题 If I have a Utilities.cs class in C#, which contains only static methods e.g. public static string DoSomething() { return "something"; } Should I make the class itself static? public static Utilities() { ... Does making the class static have any advantages? 回答1: Yes you should. It stops people from instantiating the class when they shouldn't, and makes the purpose of the class clearer. Have a read of the MSDN page for more information. You also need to mark the class as static if you want to

问题 I am interacting with an API that just has static functions, and cannot be opened up and changed. public class WindowsNativeGraphAPI { public static IEnumerable<IGraphData> GetGraphData(); public static bool DeleteGraphData(IGraphData data); } I would like to be able to pass the API into a function or constructor and comply with dependency injection (just in case we were to swap out the API later). public void GatherGraphData(IGraphAPI api) {...} To allow this API to be passed in as a

问题 I want to assign a static method to a class variable in Python, and below is what my code looks like. class Klass: classVariable = None @staticmethod def method(): print "method called" Klass.classVariable = Klass.method Klass.method() Klass.classVariable() This gave me an error at the last line, TypeError: unbound method method() must be called with Klass instance as first argument (got nothing instead). But when I change the static method to class method it works. Can anyone give me any

问题 I am trying to implement infer_class function that, given a method, figures out the class to which the method belongs. So far I have something like this: import inspect def infer_class(f): if inspect.ismethod(f): return f.im_self if f.im_class == type else f.im_class # elif ... what about staticmethod-s? else: raise TypeError("Can't infer the class of %r" % f) It does not work for @staticmethod-s because I was not able to come up with a way to achieve this. Any suggestions? Here's infer_class

问题 I have written test cases to mock static classes and methods using PowerMockito's mockStatic feature. But I am strugling to mock one static method inside another static method. I did see few examples including this but none of them actually helping me or I am not understanding the actual functionality? (I'm clueless) Eg. I have a class as below and complete code is here. public static byte[] encrypt(File file, byte[] publicKey, boolean verify) throws Exception { //some logic here PGPPublicKey

问题 There are many ways one can declare a function in javascript. One of the ways is declaring a class and a static function inside is as showed below. class className { static fucntionName() { } } another way of is declaring is through the tradition javascript style as showed below. export function functionName() { } I would like to know the advantages/disadvantages of using either of the cases. Is there any specific use cases for the static methods, why declare a class(we know that in

问题 This question already has answers here : Pointers to static methods in Python (3 answers) Closed 6 years ago . While it's fairly simple to monkeypatch instance methods to classes, e.g. class A(object): pass def a(self): print "a" A.a = a doing this with another class's @staticmethod à la class B(object): @staticmethod def b(): print "static b" A.b = B.b results in A.b() yielding a TypeError : unbound method b() must be called with A instance as first argument (got nothing instead) 回答1: Make A