A portlet might be comprised of a single or multiple models. There are no requirements, limitations, or rules specifying the number of models a portlet should contain.
We have seen that from a technical perspective, a model is a container for builder calls. Technically, there is no limit to how many builder calls a model can contain. However, this does not mean that a single model should hold all the builder calls required to construct your portlet. In fact, for commercial grade portlets, usually the best solution is accomplished through the utilization of multiple models. By doing so, builder calls can be logically organized and distributed throughout these models.
Portal and WEF architects need to consider the best patterns and architectural alternatives to efficiently identify not only the ideal number of models, but also how they relate to each other within a portlet or even the entire portal application. A well-organized model structure is crucial for the successful...