MVC: Development Mode
1. jsp history of the evolution
1. Early only servlet, can only use the response output tag data, very troublesome
2. Later, jsp, simplifies the development of Servlet, jsp if overused, that is, write a lot of java in the jsp code and write html, makes it difficult to maintain, difficult division of labor
3. later, web development java, learn mvc development model, making the program a more rational design of
MVC 2.:
1. M: Model, model. JavaBean
accomplish specific business operations, such as: a database query, encapsulate the object
2. V: View, View. JSP
impression data
3. C: Controller, controller. Servlet
get input from the user
to call the model
the data to the view on display
Advantages and disadvantages:
1. Advantages:
1 low coupling, easy maintenance, beneficial division of labor
2. high reusability
2. Disadvantages:
1. make the project architecture is complicated, high requirements for developers
Three-tier architecture: the software design architecture
1. interface layer (presentation layer): see user interface. The user can interact through the interface component and the server
2. business logic: the business logic.
3. Data Access Layer: operating a data storage file.
