Simplify Unit Testing for Spring Web Components

here is nothing more reassuring for the software engineer than having a set of executable unit tests that exercise all the aspects of the component under test. Traditionally, testing J2EE Web components has been a more difficult task than testing standalone Java objects because Web components must run in some form of the server platform and they are coupled to the specifics of the HTTP-based Web interaction.

Testability is one of the key principles behind the Spring framework (i.e., the ability to test each component in the framework regardless of its nature). In this sense, Spring was a major improvement over the core J2EE model, in which the components were hard to test outside of the container. Even in-container testing required significant and often complicated setup. (See Sidebar: Why Testability Is Important.)