determining which verb to use for method names in Java

I usually ask myself: What is this method doing? The answer dictates what the method should be called. It is completely independent of the programmer, of course. Note: If you can’t succinctly describe what the method is doing, it’s probably doing too much and should be split up. Choosing your method’s verb: Performing calculation(s): calculate … Read more

Performance of using static methods vs instantiating the class containing the methods

From here, a static call is 4 to 5 times faster than constructing an instance every time you call an instance method. However, we’re still only talking about tens of nanoseconds per call, so you’re unlikely to notice any benefit unless you have really tight loops calling a method millions of times, and you could … Read more

python: What happens when class attribute, instance attribute, and method all have the same name?

Class attributes are accessible through the class: YourClass.clsattribute or through the instance (if the instance has not overwritten the class attribute): instance.clsattribute Methods, as stated by ecatmur in his answer, are descriptors and are set as class attributes. If you access a method through the instance, then the instance is passed as the self parameter … Read more

What is premain() and how does it get called?

The premain is a mechanism associated with the java.lang.instrument package, used for loading “Agents” which make byte-code changes in Java programs. The mechanism is explained in the java.lang.instrument documentation. The gist of it is that the “agent” is deployed in a jar, and that jar has a special entry in its manifest, that tells the … Read more

Java Enum as generic type in Enum

In your method implementation PerspectiveCommands is not the enum but your type parameter, which often is called T. It thus shadows the enum of the same name like axtavt already said, thus PERSPECTIVE is unknown here. Your abstract method declaration is fine but you might use a slightly different approach. public void test(PerspectiveCommands command) would … Read more

Python : Assert that variable is instance method?

inspect.ismethod is what you want to find out if you definitely have a method, rather than just something you can call. import inspect def foo(): pass class Test(object): def method(self): pass print inspect.ismethod(foo) # False print inspect.ismethod(Test) # False print inspect.ismethod(Test.method) # True print inspect.ismethod(Test().method) # True print callable(foo) # True print callable(Test) # True … Read more

id()s of bound and unbound method objects — sometimes the same for different objects, sometimes different for the same object

Whenever you look up a method via instance.name (and in Python 2, class.name), the method object is created a-new. Python uses the descriptor protocol to wrap the function in a method object each time. So, when you look up id(C.foo), a new method object is created, you retrieve its id (a memory address), then discard … Read more

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