In a web application tracking user login and logout, which listeners would be most effective?
- HttpSessionAttributeListener
- HttpSessionListener
- ServletContextListener
- ServletRequestListener
The HttpSessionListener is most effective for tracking user login and logout in a web application as it provides notifications about session creation and destruction.
The __________ listener is useful for monitoring changes in request attributes during the lifespan of a request.
- RequestAttribute
- RequestAttributeChange
- ServletRequestAttribute
- ServletRequestAttributeListener
The ServletRequestAttributeListener is useful for monitoring changes in request attributes during the lifespan of a request.
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.
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.
Which of the following is true about ServletConfig?
- It is a configuration object
- It is a servlet class
- It is a servlet interface
- It is used for session management
ServletConfig is an interface that provides a servlet with its initialization parameters. It is used to pass configuration information to the servlet and is not a class or interface related to session management.
To pass control to the next entity in the filter chain, a filter must call the _______ method.
- continue()
- doFilter()
- forward()
- next()
To pass control to the next entity in the filter chain, a filter must call the doFilter() method, which allows the request to proceed to the next entity in the chain.
Filters can modify the __________ or __________ objects before they reach a servlet.
- request, response
- request, session
- response, context
- session, context
Filters can modify the request or response objects before they reach a servlet.
The __________ method of a filter is used for initialization.
- filterInit()
- init()
- initFilter()
- initialize()
The init() method of a filter is used for initialization.
A filter is configured in the web application's __________ file.
- config.xml
- filter.xml
- index.jsp
- web.xml
A filter is configured in the web application's web.xml file.
In what scenario would a filter be used instead of a servlet?
- For authentication and logging
- For handling HTTP requests
- For managing session state
- For processing business logic
Filters are typically used for tasks such as authentication, logging, and modifying the request and response. In scenarios where the primary purpose is not to generate a response, but to perform pre or post-processing, filters are preferred over servlets.
How can filters dynamically modify the request and response in a servlet-based application?
- Using the alter() method
- Using the doFilter() method
- Using the modify() method
- Using the transform() method
Filters can dynamically modify the request and response by implementing the doFilter() method. This method provides access to the request and response objects, allowing for manipulation before and after the request reaches the servlet.
What mechanism is used to chain multiple filters together in a web application?
- FilterChain
- FilterGroup
- FilterPipeline
- FilterSequence
The FilterChain mechanism is used to chain multiple filters together in a web application. Filters are executed in the order they are added to the chain, allowing for the sequential processing of the request and response.