JavaWeb project, among which, which technologies are the most basic and important?

the most basic and important things are Java language, object-oriented analysis design idea, design pattern and framework structure. The Java language system is huge, including multiple modules. From the perspective of WEB project application, there are four technologies: JSP, Servlet, JDBC and JavaBean(Application). Java language is a completely object-oriented language. When analyzing the business relationship of a project, some UML diagrams can be used to find out the main objects faced by business logic as soon as possible, then divide the behavior of each object, and finally realize the integration and communication between objects. The design pattern is mainly related to two-tier design pattern, three-tier design pattern and n-tier design pattern. Many Web projects adopt the three-tier development structure of MVC, namely JSP+Servlet+JavaBean.