Book Image

Design Patterns and Best Practices in Java

By : Kamalmeet Singh, Adrian Ianculescu, Lucian-Paul Torje
Book Image

Design Patterns and Best Practices in Java

By: Kamalmeet Singh, Adrian Ianculescu, Lucian-Paul Torje

Overview of this book

Having a knowledge of design patterns enables you, as a developer, to improve your code base, promote code reuse, and make the architecture more robust. As languages evolve, new features take time to fully understand before they are adopted en masse. The mission of this book is to ease the adoption of the latest trends and provide good practices for programmers. We focus on showing you the practical aspects of smarter coding in Java. We'll start off by going over object-oriented (OOP) and functional programming (FP) paradigms, moving on to describe the most frequently used design patterns in their classical format and explain how Java’s functional programming features are changing them. You will learn to enhance implementations by mixing OOP and FP, and finally get to know about the reactive programming model, where FP and OOP are used in conjunction with a view to writing better code. Gradually, the book will show you the latest trends in architecture, moving from MVC to microservices and serverless architecture. We will finish off by highlighting the new Java features and best practices. By the end of the book, you will be able to efficiently address common problems faced while developing applications and be comfortable working on scalable and maintainable projects of any size.
Table of Contents (15 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Introducing functional programming


During the 1930s, the mathematician Alonzo Church developed lambda calculus. This was the starting point for the functional programming paradigm, since it provided the theoretical grounds. The next step was the design of LISP (short for List Programming) in 1958, by John McCarthy. LISP is the first functional programming language, and some of its flavors, such as Common LISP, are still used today.

In functional programming (often abbreviated to FP), functions are first-class citizens; this means that software is built by composing functions, rather than objects, as OOP. This is done in a declarative way, Tell don't ask, by composing functions, promoting immutability, and avoiding the side effects and shared data. This leads to a more concise code that is resilient to changes, predictable, and easier to maintain and read by business people.

Functional code has a higher signal-to-noise ratio; we have to write less code to achieve the same thing as in OOP. By...