flowchart TD
A[Client Request] --> B[Servlet Container<br>Tomcat/Undertow/Jetty]
B --> C[Servlet Filters<br>Security, CORS, Logging]
subgraph SpringBootApp [Spring Boot Application]
C --> D[DispatcherServlet<br>Front Controller]
D --> E{Handler Mapping}
E --> F[Selected Controller]
F --> G[Interceptors PreHandle]
G --> H[Controller Method Execution]
H --> I[Service Layer]
I --> J[Repository Layer]
J --> K[Database]
K --> J
J --> I
I --> H
H --> L[Interceptors PostHandle]
L --> M[View Resolution]
M --> N[Response Rendering]
N --> O[Interceptors AfterCompletion]
end
O --> P[Servlet Filters<br>Response Processing]
P --> Q[HTTP Response]
Q --> R[Client]
style SpringBootApp fill:dark,stroke:#01579b,stroke-width:2px
style C fill:red,stroke:#ff6f00
style P fill:red,stroke:#ff6f00
- HTTP request arrives at the server
- Request contains method, headers, parameters, and body
- Request received by embedded servlet container (Tomcat, Undertow, or Jetty)
- Container creates HttpServletRequest and HttpServletResponse objects
- Security Filters: Authentication and authorization (Spring Security)
- CORS Filters: Cross-origin request handling
- Logging Filters: Request logging and monitoring
- Character Encoding Filters: Request encoding setup
- Each filter can process, modify, or reject the request
- Front controller receives the filtered request
- Central entry point for Spring MVC framework
- Determines which controller method should handle the request
- Based on URL patterns, HTTP methods, and other conditions
- Custom pre-processing logic
- Authentication checks
- Request logging
- Can short-circuit processing by returning false
- Parameter binding (path variables, request params, request body)
- Validation (if applicable)
- Business logic invocation
- Service layer method calls
- Business logic implementation
- Transaction management
- Additional validation
- Data access operations
- Database interactions
- ORM operations (if using JPA/Hibernate)
- SQL query execution
- Data retrieval or modification
- Transaction management
- Return from repository to service layer
- Return from service to controller
- Response object construction
- Post-processing after controller execution
- Response modification
- Additional logging
- View name to actual view resolution
- Template processing (Thymeleaf, JSP, etc.)
- Model data binding to view
- Content generation (JSON, HTML, XML)
- Response body creation
- HTTP status and header setting
- Request completion callbacks
- Cleanup operations
- Final logging
- Response modification filters
- Compression filters
- Additional response headers
- Response sent back through servlet container
- Container manages connection and response writing
- Client receives HTTP response
- Browser or client application processes response
- Execute before and after Spring MVC processing
- Can intercept and modify requests and responses
- Operate at the servlet container level
- Central dispatcher for HTTP request handling
- Coordinates all request processing components
- Manages handler mapping, view resolution, etc.
- Maps requests to handler methods
- Supports various mapping strategies:
- Annotation-based (@RequestMapping)
- Controller class name patterns
- Programmatic registration
- Three interception points:
- preHandle: Before controller execution
- postHandle: After controller but before view rendering
- afterCompletion: After complete request processing
- @ControllerAdvice for global exception handling
- @ExceptionHandler for controller-specific exceptions
- HandlerExceptionResolver for custom exception resolution
- ViewResolver strategies for different template engines
- Content negotiation for different response types
- Model data binding to views
