Design Patterns Explained: A New Perspective on Object-Oriented Design

Learning the Abstract Factory Pattern: An Example

Suppose I have been given the task of designing a computer system to display and print shapes from a database. The type of resolution to use to display and print the shapes depends on the computer that the system is currently running on: the speed of its CPU and the amount of memory that it has available. My system must be careful about how much demand it is placing on the computer.

The challenge is that my system must control the drivers that it is using: low-resolution drivers in a less-capable machine and high-resolution drivers in a high-capacity machine, as shown in Table 10-1.

Table 10-1. Different Drivers for Different Machines

For driver…	In a low-capacity machine, use…	In a high-capacity ...