The reason for the Math object is simple: “because Java does it”. Not the best of reasons, but here we are. I guess things made more sense back then, before Douglas Crockford started his campaign to suppress half the language*. Originally you were “allowed”, or meant, to do things like this: with (Math) { var … Read more
Polymorphism can be achieved through overriding. Put in short words, polymorphism refers to the ability of an object to provide different behaviors (use different implementations) depending on its own nature. Specifically, depending on its position in the class hierarchy. Method Overriding is when a method defined in a superclass or interface is re-defined by one … Read more
I am thinking it will impact performance. I doubt that this will be true. Assuming that the application reads the configuration file just once at startup, the time taken to read the file is probably irrelevant to your application’s overall performance. Indeed, the longer the application runs, the less important startup time will be. Standard … Read more
I just bumped into this problem today (2020-12-09); I had to change a number of subpackages for Python 3.8. Perhaps an alternative to the other solutions here is the following, inspired by the excellent answer here to a similar question, as well as @MadPhysicist’s answer on this page: from enum import Enum, EnumMeta class MetaEnum(EnumMeta): … Read more
The two int variables are defined in the header file. This means that every source file which includes the header will contain their definition (header inclusion is purely textual). The of course leads to multiple definition errors. You have several options to fix this. Make the variables static (static int WIDTH = 1024;). They will … Read more
The point of getters and setters, regardless of language, is to hide the underlying variable. This allows you to add verification logic when attempting to set a value – for example, if you had a field for a birth date, you might only want to allow setting that field to some time in the past. … Read more
A local variable is the variable you declare in a function. A member variable is the variable you declare in a class definiton.
I think there are no specific design guidelines for this. But some of the design principles do talk about method creation. DRY ( don’t repeat yourself) is a guiding principle when comes to method creation. You group similar logic in a single method so that you don’t duplicate them all over your code and thus … Read more