Book Image

Hands-On Design Patterns with Delphi

By : Primož Gabrijelčič
Book Image

Hands-On Design Patterns with Delphi

By: Primož Gabrijelčič

Overview of this book

Design patterns have proven to be the go-to solution for many common programming scenarios. This book focuses on design patterns applied to the Delphi language. The book will provide you with insights into the language and its capabilities of a runtime library. You'll start by exploring a variety of design patterns and understanding them through real-world examples. This will entail a short explanation of the concept of design patterns and the original set of the 'Gang of Four' patterns, which will help you in structuring your designs efficiently. Next, you'll cover the most important 'anti-patterns' (essentially bad software development practices) to aid you in steering clear of problems during programming. You'll then learn about the eight most important patterns for each creational, structural, and behavioral type. After this, you'll be introduced to the concept of 'concurrency' patterns, which are design patterns specifically related to multithreading and parallel computation. These will enable you to develop and improve an interface between items and harmonize shared memories within threads. Toward the concluding chapters, you'll explore design patterns specific to program design and other categories of patterns that do not fall under the 'design' umbrella. By the end of this book, you'll be able to address common design problems encountered while developing applications and feel confident while building scalable projects.
Table of Contents (18 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Index

Builder


The last pattern from this chapter, builder, helps with creating complex objects or their representations. The general idea behind the pattern is to separate such a process into two parts: one gives instructions to an abstract builder interface, and another converts the instructions into a concrete representation. This allows us to create multiple representations from the same construction process.

Note

The builder pattern is similar to an automated coffee/tea machine that always follows the same build process: put a cup on the tray, insert the correct beverage into the system, flow hot water through the system into the cup, and beep at the end. While the build process is always the same, the end result depends on a concrete implementation of step two.

The builder pattern is very similar to the abstract factory pattern. In both cases, the shared class uses an abstract interface to execute a task. The difference is that the builder pattern is focused on step-by-step instructions that...