In this part of the migration guide we address the differences of the APIs in Struts Tiles and Tiles 2.
If you are a Tiles extension developer and you want to convert your existing extension, see Tiles extensions migration guide.
In Tiles 2, the concept of a Tiles Controller, i.e. an object that it is invoked before rendering a definition, has been replaced with ViewPreparer.
The classes that implement the Controller interface must now implement the new ViewPreparer interface, or extend the ViewPreparerSupport class.
The ComponentContext, i.e. the Tiles-specific context in which the current attribute values are stored, has been renamed to AttributeContext.
The method getAttribute returns an Attribute, and not an Attribute Value, i.e. a simple object.