Can a single class implement multiple listener interfaces in Servlets? If so, what are the considerations?
- No, a class can only implement one listener interface in Servlets.
- No, it depends on the version of the Servlet API.
- Yes, a class can implement multiple listener interfaces.
- Yes, but it is not recommended due to potential conflicts.
Yes, a single class can implement multiple listener interfaces in Servlets. However, it's essential to carefully consider potential conflicts and ensure that the class can handle events from all implemented interfaces.
The __________ interface is used to receive events about changes to the servlet context's attribute list.
- ServletAttributeEvent
- ServletContextAttributeEvent
- ServletContextEvent
- ServletEvent
The ServletContextAttributeEvent interface is used to receive events about changes to the servlet context's attribute list.
To track the creation and destruction of HttpSession objects, the _________ interface is implemented.
- HttpSessionEvent
- HttpSessionListener
- HttpSessionTracker
- SessionLifecycleListener
The HttpSessionListener interface is implemented to track the creation and destruction of HttpSession objects.
When a session is passivated or activated, the __________ interface provides the necessary notifications.
- ActivationEventListener
- HttpSessionActivationEvent
- SessionActivationListener
- SessionPassivationEvent
The HttpSessionActivationEvent interface provides the necessary notifications when a session is passivated or activated.
What is the primary purpose of using filters in web applications?
- To handle HTTP requests and responses
- To manage session information
- To perform tasks before or after the request is handled by a servlet
- To store data in the client's browser
The primary purpose of using filters in web applications is to perform tasks before or after the request is handled by a servlet, allowing for common processing tasks to be centralized.
At which point in the request processing are filters applied in a web application?
- After the response is generated by the servlet
- At the end of the servlet lifecycle
- Before the request reaches the servlet
- During servlet initialization
Filters are applied before the request reaches the servlet, allowing for pre-processing of the request or post-processing of the response.
Which interface must a class implement to act as a filter in a web application?
- Filter
- HttpFilter
- Servlet
- WebFilter
To act as a filter in a web application, a class must implement the Filter interface.
What is the correct order of method calls in the lifecycle of a filter?
- destroy(), init(), doFilter()
- doFilter(), init(), destroy()
- init(), destroy(), doFilter()
- init(), doFilter(), destroy()
The correct order of method calls in the lifecycle of a filter is init(), doFilter(), destroy(). Filters are initialized first, then the doFilter() method is called for each request, and finally, the destroy() method is called when the filter is removed from service.
The _________ listener is invoked when an attribute is added, removed, or replaced in a session.
- HttpSessionAttribute
- HttpSessionBinding
- HttpSessionEvent
- SessionAttributeListener
The HttpSessionBinding listener is invoked when an attribute is added, removed, or replaced in a session.
To respond to events like the initialization or destruction of the ServletContext, use the _________ listener.
- ContextInitializationListener
- ServletConfigListener
- ServletContextEvent
- ServletContextListener
Use the ServletContextListener to respond to events like the initialization or destruction of the ServletContext.