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


This chapter provided an overview of structural patterns.

This chapter opened with a composite pattern. This pattern describes how to create an interface that doesn't make a distinction between a basic object and a composite object that is composed of more basic or composite objects. It is especially appropriate when we are operating on tree structures.

The next pattern was flyweight. It is different than other structural patterns because of its focus on memory usage. The flyweight pattern tells us how to share static data between multiple objects to reduce memory usage. This chapter also discussed a practical implementation of this pattern: a string interning, and explored Delphi concepts of equality comparers and hashers.

Next on the list was marker interfaces. This pattern enables metadata annotation in languages that don't provide specific metadata features. In later years, it was mostly replaced with language-specific approaches. In Delphi, we can use attributes to annotate metadata...