O'Reilly logo

Professional Plone Development: Building robust, content-centric web applications with Plone 3, an open source Content Management System by Martin Aspeli

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Acquisition and Skin Layers

Acquisition is simultaneously one of best and worst features of Zope 2. Consider that Zope manages a hierarchy of objects, each of which (except the Zope application root) has exactly one parent. In traditional object-oriented programming, a subclass can gain attributes and methods from its super-classes. Zope 2 acquisition wraps Python objects retrieved from the ZODB or being found during URL traversal in such a way that they can also acquire attributes from their parents in the hierarchy. For example, some code may read:

context.getDefault()

Here, context may be the current content object, and getDefault() could be a method on its containing folder, or another folder higher up. Closer attributes always take precedence. ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required