Shallow copies duplicate as little as possible. A shallow copy of a collection is a copy of the collection structure, not the elements. With a shallow copy, two collections now share the individual elements. Deep copies duplicate everything. A deep copy of a collection is two collections with all of the elements in the original … Read more
The bit shifting operators do exactly what their name implies. They shift bits. Here’s a brief (or not-so-brief) introduction to the different shift operators. The Operators >> is the arithmetic (or signed) right shift operator. >>> is the logical (or unsigned) right shift operator. << is the left shift operator, and meets the needs of … Read more
Developers are often confused by what a callback is because of the name of the damned thing. A callback function is a function which is: accessible by another function, and is invoked after the first function if that first function completes A nice way of imagining how a callback function works is that it is … Read more
Dependency Injection is passing dependency to other objects or framework( dependency injector). Dependency injection makes testing easier. The injection can be done through constructor. SomeClass() has its constructor as following: Problem: If myObject involves complex tasks such as disk access or network access, it is hard to do unit test on SomeClass(). Programmers have to … Read more
In computing, an idempotent operation is one that has no additional effect if it is called more than once with the same input parameters. For example, removing an item from a set can be considered an idempotent operation on the set. In mathematics, an idempotent operation is one where f(f(x)) = f(x). For example, the … Read more