Which listener interface is implemented to track session creation and destruction?
- HttpSessionListener
- ServletContextAttributeListener
- ServletContextListener
- ServletRequestListener
The HttpSessionListener interface is implemented to track session creation and destruction events in servlets.
What type of listener is used to monitor changes in ServletContext attributes?
- HttpSessionAttributeListener
- HttpSessionListener
- ServletContextAttributeListener
- ServletRequestListener
The ServletContextAttributeListener is used to monitor changes in ServletContext attributes.
Which method is used to get a reference to the ServletContext?
- getContext()
- getServletConfig()
- getServletContext()
- init()
The getServletContext() method is used to obtain a reference to the ServletContext. It is typically called within a servlet using the this.getServletContext() or getServletContext() to access the context information.
How should filters be configured to apply only to certain URL patterns in a web application?
- Configure in the web.xml file
- Filters automatically apply to all URLs
- Specify URL patterns in the filter mapping in the deployment descriptor
- Use annotations in the filter class
Filters should be configured to apply only to certain URL patterns by specifying those patterns in the filter mapping in the deployment descriptor (web.xml).
If a filter needs to modify the response header of all responses, which method should be primarily used?
- doFilter()
- doResponse()
- init()
- modifyHeader()
To modify the response header of all responses, the filter should primarily use the doFilter() method, where manipulation of both request and response is possible.
A filter is implemented to log request details. Where should this logging take place in the filter's methods?
- destroy()
- doFilter()
- filterConfig()
- init()
The logging of request details in a filter should take place within the doFilter() method, which is called for each request and allows processing of the request and response.
For security purposes, filters are often used to implement __________ and __________ controls.
- authentication, authorization
- authentication, validation
- authorization, authentication
- validation, authorization
For security purposes, filters are often used to implement authentication and authorization controls, ensuring proper user identification and access rights in a web application.
Filters can be applied to __________ or __________ resources in a web application.
- dynamic, JSP
- servlets, dynamic
- servlets, static
- static, dynamic
Filters can be applied to both servlets and static resources or servlets and dynamic resources in a web application.
The listener interface _________ is used to listen for request attribute changes.
- EventListener
- HttpSessionAttributeListener
- ServletContextAttributeListener
- ServletRequestAttributeListener
The correct answer is HttpSessionAttributeListener. This interface is used to listen for changes to attributes in a session, allowing developers to respond to attribute addition, removal, or replacement.
In which scenario would you use HttpSessionIdListener?
- To customize the session ID generation process.
- To manage session activation and passivation.
- To monitor changes in session attributes.
- To track the creation and destruction of sessions.
HttpSessionIdListener is used in scenarios where you want to customize the session ID generation process in servlets. It provides a way to influence how session IDs are created and assigned to user sessions.
How does the HttpSessionActivationListener interface help in servlets?
- It is used to activate and deactivate sessions in the HttpSession.
- It is used to listen to attribute changes in the HttpSession.
- It is used to listen to session activation and passivation events.
- It is used to manage session IDs in the HttpSession.
The HttpSessionActivationListener interface is specifically designed to listen to session activation and passivation events, allowing servlets to perform tasks when sessions are activated or passivated.
What is the difference between ServletContextListener and ServletContextAttributeListener?
- Both can be used to listen to events in the ServletContext.
- ServletContextAttributeListener listens to changes in the ServletContext, while ServletContextListener specifically listens to attribute changes in the ServletContext.
- ServletContextListener listens to changes in the ServletContext, while ServletContextAttributeListener specifically listens to attribute changes in the ServletContext.
- They serve the same purpose and can be used interchangeably.
ServletContextListener is used to detect changes in the ServletContext, whereas ServletContextAttributeListener focuses on changes in attributes within the ServletContext.