PHP Objects, Patterns, and Practice, Fourth Edition

CHAPTER 9

Generating Objects

Creating objects is a messy business. So many object-oriented designs deal with nice, clean abstract classes, taking advantage of the impressive flexibility afforded by polymorphism (the switching of concrete implementations at runtime). To achieve this flexibility, though, I must devise strategies for object generation This is the topic I will look at in this chapter.

This chapter will cover:

• The Singleton pattern: A special class that generates one and only one object instance
• The Factory Method pattern: Building an inheritance hierarchy of creator classes
• The Abstract Factory pattern: Grouping the creation of ...