Let’s explain dependency injection (one of the most used design patterns) with a very good example found in the book “Spring in Action, 4th Edition”.
Singleton pattern is one of the simplest design patterns in Java. This type of design pattern comes under creational pattern as this pattern provides one of the best ways to create an object.
In object-oriented computer programming, the term SOLID is an acronym for five designs principles intended to make software designs more understandable, flexible and maintainable. The principles are a subset of many principles promoted by Robert C. Martin. Thought they apply to an object-oriented design, the SOLID principles can also form a core philosophy for methodologies such as agile development or adaptive software development. The SOLID acronym was introduced by Michael Feathers.