12.1. Design patterns and web technologies

Design patterns are generally accepted solutions that typically work for common problems. They help avoid “Rediscovering the Wheel Syndrome,” and offer advice for when and how they should be used. Sun’s Java Blueprints Program provides a catalog of core design patterns for building Java EE applications. You can access the catalog of Java patterns online at http://java.sun.com/blueprints/corej2eepatterns/Patterns/index.html.

We’ll introduce some important design patterns and technologies in this section by tier: