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

Chapter 9. Thread pool, Messaging, Future and Pipeline

Multithreaded programming is complicated. I hope that the previous chapter has sufficiently demonstrated how hard it is to coordinate multiple threads that work on shared data. There are just so many possibilities for writing code that doesn't always work correctly or to implement a fix that slows a program down so much that the new and improved parallel solution is actually slower than the original single-threaded code.

In this chapter, I will continue exploring design patterns (with a bit of architectural thinking thrown in) in a completely different direction. Instead of working on shared data, the patterns from this chapter will be used to write parallel tasks that are independent of each other. To achieve that, they use multiple copies of data and communicate with messages.

Introducing such patterns, however, often requires a redesign of the program architecture, which may be an impossible task in some situations. To help with such...