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


In this chapter, we have examined four more behavioral patterns. They are a bit more complex than the patterns from the previous chapter, but they also help a lot with organizing the code and are well worth your consideration.

The iterator pattern is well-known to Delphi programmers. Most of you know how to write a loop, even though the implementation details hiding behind this construct may not be your biggest concern. In this chapter, we have also explored the other part of iterators, namely, how to use them as a tool for writing generic algorithms.

This chapter continued with the visitor pattern, which is in some aspects iterator's counterpart. Unlike the iterator, this pattern wasn't designed to walk over data structures, but to iterate over complex object structures. With a proper implementation, it allows us to open a small window into object internals and use it to write extensions that enhance existing objects.

The observer pattern, also know as publish-subscribe, is...