static-methods

I'm trying to write a python class which uses a decorator function that needs information of the instance state. This is working as intended, but if I explicitly make the decorator a staticmetod, I get the following error: Traceback (most recent call last): File "tford.py", line 1, in <module> class TFord(object): File "tford.py", line 14, in TFord @ensure_black TypeError: 'staticmethod' object is not callable Why? Here is the code: class TFord(object): def __init__(self, color): self.color = color @staticmethod def ensure_black(func): def _aux(self, *args, **kwargs): if self.color == 'black':

When I attempt to use a static method from within the body of the class, and define the static method using the built-in staticmethod function as a decorator, like this: class Klass(object): @staticmethod # use as decorator def _stat_func(): return 42 _ANS = _stat_func() # call the staticmethod def method(self): ret = Klass._stat_func() + Klass._ANS return ret I get the following error: Traceback (most recent call last):<br> File "call_staticmethod.py", line 1, in <module> class Klass(object): File "call_staticmethod.py", line 7, in Klass _ANS = _stat_func() TypeError: 'staticmethod' object is

When is it considered poor practice to use the static keyword in Java on method signatures? If a method performs a function based upon some arguments, and does not require access to fields that are not static, then wouldn't you always want these types of methods to be static? One reason why you may not want it to be static is to allow it to be overridden in a subclass. In other words, the behaviour may not depend on the data within the object, but on the exact type of the object. For example, you might have a general collection type, with an isReadOnly property which would return false in

I have concept of static variables but what are the benefits of static methods in a class. I have worked on some projects but I did not make a method static. Whenever I need to call a method of a class, I create an object of that class and call the desired method. Q: Static variable in a method holds it's value even when method is executed but accessible only in its containing method but what is the best definition of static method? Q: Is calling the static method without creating object of that class is the only benefit of static method? Q: What is the accessible range for static method?

I tend to declare as static all the methods in a class when that class doesn't require to keep track of internal states. For example, if I need to transform A into B and don't rely on some internal state C that may vary, I create a static transform. If there is an internal state C that I want to be able to adjust, then I add a constructor to set C and don't use a static transform. I read various recommendations (including on StackOverflow) NOT to overuse static methods but I still fail to understand what it wrong with the rule of thumb above. Is that a reasonable approach or not? John Millikin

I just did a little experiment: public abstract class MyClass { private static int myInt = 0; public static int Foo() { return myInt; } public static int Foo(int n) { myInt = n; return bar(); } private static int bar() { return myInt; } } and then I ran: MessageBox.Show(MyClass.Foo().ToString()); MessageBox.Show(MyClass.Foo(3).ToString()); MessageBox.Show(MyClass.Foo().ToString()); MessageBox.Show(MyClass.Foo(10).ToString()); MessageBox.Show(MyClass.Foo().ToString()); The results I expected were 0, 3, 0, 10, 0. To my surprise, I got 0, 3, 3, 10, 10. How long do these changes persist for? The