Welcome to part two of the series "Abstract classes in PHP." In three tutorials, this series introduces the key concepts of abstract classes in PHP 4-PHP 5, and explores their application and use in different object-oriented development environments. Whether you're an experienced PHP developer wanting to fill in some gaps related to abstract classes, or only a beginner starting to taste the power of object-based programming in PHP, hopefully you'll find this series enjoyable and instructive.
They take a moment and look at how their example will be structured before jumping into the code. After that, they creat subclasses of the parent, defining the resultProcessor and fileProcessor classes. At the end, they combine them, creating a class that can parse data pushed into it (such as parsing out an XML file).