Top-Down Integration is a systematic approach to integration testing in software development where the top-level modules are tested first. This method ensures that the higher-level functionality is validated early in the testing process, allowing for the identification and resolution of major issues at the top of the module hierarchy before moving down to the lower-level components. By starting from the top, this approach promotes early detection of critical design flaws and provides a clear understanding of the overall system architecture.
In a Top-Down Integration process, stubs are used to simulate the behavior of lower-level modules that have not yet been integrated. These stubs act as temporary placeholders, enabling testers to focus on the interactions and data flow between the upper modules without waiting for the development of the entire system. This incremental approach facilitates a structured and organized testing phase, making it easier to isolate and fix defects as they are discovered. Overall, Top-Down Integration helps in achieving a more efficient and manageable integration testing cycle, leading to a robust and reliable software product.
