MVC basic

Question 1

How Spring MVC Works behind the scenes

Answer 1

Question 2

Components of a Spring MVC Application

Answer 2

• A set of web pages to layout UI components

• A collection of Spring beans (controllers, services, etc…)

• Spring configuration (XML, Annotations or Java)

Question 3

Spring MVC Front Controller

Answer 3

Spring MVC Front Controller

Front controller known as DispatcherServlet Part of the Spring Framework

Already developed by Spring Dev Team


You as a developer will create

Model objects (orange)

View templates (dark green)

Controller classes (yellow)

Question 4

Spring MVC Front Controller

Answer 4

Question 5

What is a Controller?

Answer 5

• Code created by developer

• Contains your business logic
  
  • Handle the request
  • Store/retrieve data (db, web service…)
  • Place data in model

• Send to appropriate view template

Question 6

Model

Answer 6

• Model: contains your data

• Store/retrieve data via backend systems
  
  • database, web service, etc…
  • Use a Spring bean if you like

• Place your data in the model
  
  • Data can be any Java object/collection

Question 7

View Template

Answer 7

• Spring MVC is flexible
  
  • Supports many view templates

• Most common is JSP + JSTL

• Developer creates a page
  
  • Displays data

Question 8

Spring MVC Configuration Process - Part 1

Answer 8

Add configurations to file: WEB-INF/web.xml

• Configure Spring MVC Dispatcher Servlet

• Set up URL mappings to Spring MVC Dispatcher Servlet

Question 9

Spring MVC Configuration Process - Part 2

Answer 9

Add configurations to file: WEB-INF/spring-mvc-demo-servlet.xml

• Add support for Spring component scanning

• Add support for conversion, formatting and validation

• Configure Spring MVC View Resolve

Question 10

Spring MVC example

Answer 10

Question 11

Development Process

Answer 11

1. Create Controller class

2. Define Controller method

3. Add Request Mapping to Controller method

4. Return View Name

5. Develop View Page

Question 12

Step 1: Create Controller class

Answer 12

Annotate class with @Controller

• @Controller inherits from @Component … supports scanning

@Controller

public class HomeController { }

Question 13

Step 2: Define Controller method

Answer 13

@Controller
public class HomeController {

public String showMyPage() { …

}

}

Question 14

Step 3: Add Request Mapping to Controller method

Answer 14

@Controller
public class HomeController {

@RequestMapping(“/”) public String showMyPage() {

return “main-menu”; }

}

Question 15

Find View Page Magic

Answer 15

Question 16

Step 5: Develop View Page

Answer 16

File: /WEB-INF/view/main-menu.jsp

Spring MVC Demo - Home Page