tailieunhanh - Apress Pro Apache Struts with Ajax phần 2

Tương tự như các HttpContext trong , HttpListenerContext cung cấp truy cập cho các đối tượng HttpListenerRequest và HttpListenerResponse, vì vậy bước đầu tiên trong việc xử lý một yêu cầu nên luôn luôn được để có được bối cảnh này. Tiếp theo, mã sử dụng một phương tiện rất đơn giản xác định URL yêu cầu. | CHAPTER 2 Struts Fundamentals Building a web-based application can be one of the most challenging tasks for a development team. Web-based applications often encompass functionality and data pulled from multiple IT systems. Most of the time these systems are built on a variety of heterogeneous software and hardware platforms. Hence the question that the team always faces is how do we build web applications that are extensible and maintainable even as they get more complex Most development teams attack the complexity by breaking the application into small manageable parts that can communicate with one another via well-defined interfaces. Generally this is done by breaking the application logic into three basic tiers the presentation tier business logic tier and data access tier. By layering the code into these three tiers the developers isolate any changes made in one tier from the other application tiers. However simply grouping the application logic into three categories is not enough for medium to large projects. When coordinating a web-based project of any significant size the application architect for the project must ensure that all the developers write their individual pieces to a standard framework that their code will plug into. If they do not the code base for the application will be in absolute chaos because multiple developers will implement their own pieces using their own development style and design. The solution is to use a generalized development framework that has specific plug-in points for each of the major pieces of the application. However building an application development framework from the ground up entails a significant amount of work. It also commits the development team to build and support the framework. Framework support forces the development team to exhaust resources that could otherwise be used for building applications. The next three chapters of this book introduce you to a readily available alternative for building your own web .