Model-View-Presenter In MVP, the Presenter contains the UI business logic for the View. All invocations from the View delegate directly to the Presenter. The Presenter is also decoupled directly from the View and talks to it through an interface. This is to allow mocking of the View in a unit test. One common attribute of … Read more
Byte: Today, a byte is almost always 8 bit. However, that wasn’t always the case and there’s no “standard” or something that dictates this. Since 8 bits is a convenient number to work with it became the de facto standard. Word: The natural size with which a processor is handling data (the register size). The most common word sizes … Read more
Are all statements also expressions? “Wherever JavaScript expects a statement, you can also write an expression. Such a statement is called an expression statement. The reverse does not hold: you cannot write a statement where JavaScript expects an expression. For example, an if statement cannot become the argument of a function.” This is comes from … Read more
Coroutines and concurrency are largely orthogonal. Coroutines are a general control structure whereby flow control is cooperatively passed between two different routines without returning. The ‘yield’ statement in Python is a good example. It creates a coroutine. When the ‘yield ‘ is encountered the current state of the function is saved and control is returned … Read more
Anti-patterns are certain patterns in software development that are considered bad programming practices. As opposed to design patterns which are common approaches to common problems which have been formalized and are generally considered a good development practice, anti-patterns are the opposite and are undesirable. For example, in object-oriented programming, the idea is to separate the software into small … Read more
JLS-8.3.1.1. static Fields says (in part) A static field, sometimes called a class variable, is incarnated when the class is initialized (§12.4). JLS-4.12.4. final Variables says (in part) A constant variable is a final variable of primitive type or type String that is initialized with a constant expression (§15.28) tl;dr Putting that together, a class constant is a static final field.
In simple words, a loop invariant is some predicate (condition) that holds for every iteration of the loop. For example, let’s look at a simple for loop that looks like this: In this example it is true (for every iteration) that i + j == 9. A weaker invariant that is also true is that i >= 0 && … Read more
You are talking about two different (yet similar) concepts in computer science; multiprocess, and multithreading. Here is some compilation of questions/answers that might be useful: Multiprocessing — Wikipedia Multiprocessing is the use of two or more central processing units (CPUs) within a single computer system.The term also refers to the ability of a system to … Read more
The Wikipedia Example Looks like the diameter is 3 to me by definition. The longest shortest paths have length of 3 edges, e.g. between 6-1 and 6-2. The Mesh Example Here’s your second definition, with some typographical correction so that it makes sense: Diameter D of a network is defined as the longest path of the shortest paths between any … Read more
Referring more generally to the Container pattern (of which an enterprise Java container could be considered a specialization), the book Server Component Patterns by M.Volter, et al. offers the following: [A CONTAINER provides] an execution environment that is responsible for adding the technical concerns to the COMPONENTS…Conceptually, it wraps the COMPONENTS, thus giving clients the … Read more