static-methods

Can someone please explain how the following syntax works? public static <K, V> HashMap<K, V> getMap(){ return new HashMap<K, V>(); } As in, if this method was implemented in a non instantiable util class of my own this can be used as a static factory method to create map instances, right? Map<Integer, String> myMap = MyUtil.getMap(); would then return a new HashMap with Integer keys and String values for its entries, am I right? If so, how are the types of the key and entry of map being realized by the compiler and VM? I would really appreciate if someone could explain how Java does this. You

Simmilar question (related with Python2: Python: check if method is static ) Lets concider following class definition: class A: def f(self): return 'this is f' @staticmethod def g(): return 'this is g' In Python 3 there is no instancemethod anymore, everything is function, so the answer related to Python 2 will not work anymore. As I told, everything is function, so we can call A.f(0) , but of course we cannot call A.f() (argument missmatch). But if we make an instance a=A() and we call a.f() Python passes to the function A.f the self as first argument. Calling a.g() prevents from sending it

I have a general question...when should i be using static classes or static methods?.. I know the idea that static methods can be called without instantiating...and static classes should only be used for static methods?...but are there any performance concerns also with it...and when should they be preferred over instance methods and classes?..If someone could just briefly mention when i should opt for using them and when i should avoid them? Leniel Maccaferri I think the following two links offer a clear answer for what you're looking for. Take a look at them: For static classes: When to Use

assume following class definition: class A: def f(self): return 'this is f' @staticmethod def g(): return 'this is g' a = A() So f is a normal method and g is a static method. Now, how can I check if the funcion objects a.f and a.g are static or not? Is there a "isstatic" funcion in Python? I have to know this because I have lists containing many different function (method) objects, and to call them I have to know if they are expecting "self" as a parameter or not. MacSanhe I happens to have a module to solve this. And it's Python2/3 compatible solution. And it allows to test with method

I was just discussing about calling static methods using class name with my friend and tried out this code and expected it to throw NPE at runtime.but as it turn out it dint. i just want to understand the execution order. public class One { public static void method() { System.out.println("in static one"); } } public class Two { static One o; public static void main(String[] args) { o.method(); // expected NPE here, as o is null } } I know that static methods should be invoked with their class name, I even know that IDE's would give a compiler warning when we call static methods with an

I am confused about garbage collection process on objects. object A = new object(); object B = A; B.Dispose(); By calling a Dispose on variable B only, the created object will not be garbage collected as the object is still has referenced by A. Now does the following code work same as above? public static image Test1() { Bitmap A = new Bitmap(); return A; } Now I call this static function from some other method. public void TestB() { Bitmap B = Test1(); B.Dispose(); } The static function Test1 returned a reference to the Bitmap object. The reference is saved in another variable B. By calling a

I am developing C# and asp.net web application. I have general class called utilities, I have lot of public and static variables in this public utilities class. Since this number is gradually increasing, I want to know is it good practice to store utilities methods and variable as public static. Example of my code public class utilities { public static string utilVariable1 = "Myvalue"; public static string utilVariable2 = "Myvalue"; public static string utilVariable3 = "Myvalue"; : public static string utilVariableN = "Myvalue"; public static string UtilMethod1() { //do something } public

I'm getting an error when I attempt to use the following static function. Error: Expected class, delegate, enum, interface, or struct Function (and class): namespace MyNamespace { public class MyClass { // Some other static methods that use Classes, delegates, enums, interfaces, or structs public static string MyFunc(string myVar){ string myText = myVar; //Do some stuff with myText and myVar return myText; } } } This is causing the compiler to angrily (in red) underline the string part of public static string . So, I assume this means string is not a class, delegate, enum, interface, or struct