What is the correct order of method invocation in a filter's lifecycle?

  • destroy(), init(), doFilter()
  • doFilter(), init(), destroy()
  • init(), destroy(), doFilter()
  • init(), doFilter(), destroy()
The correct order of method invocation in a filter's lifecycle is init(), doFilter(), and destroy().

Describe how you would configure a filter to initialize with predefined parameters.

  • Implement the init() method in the filter
  • Set parameters in the doFilter() method
  • Use a configuration file
  • Use the in the deployment descriptor
To configure a filter with predefined parameters, use the element in the deployment descriptor (web.xml) to specify initialization parameters. These parameters can be accessed in the filter using the getInitParameter() method.

How does the load-on-startup element in web.xml affect a servlet's lifecycle?

  • It controls the number of instances created for a servlet when handling client requests.
  • It decides whether a servlet should be loaded automatically or on demand.
  • It determines the order in which servlets are initialized when the application starts.
  • It specifies the maximum number of times a servlet can be loaded during the application's lifecycle.
The load-on-startup element in the web.xml file specifies the order in which servlets should be initialized when the application starts. Servlets with lower values are initialized first.

How would you ensure a filter only processes requests for a specific servlet?

  • Check the servlet name in the configuration
  • Set a specific attribute in the request
  • Use if conditions in the doFilter() method
  • Use the url-pattern in the filter mapping
To ensure a filter processes requests for a specific servlet, configure the filter mapping in the deployment descriptor (web.xml) using the url-pattern element with the appropriate servlet mapping.

If a filter needs to perform different actions based on whether the request is an HTTP GET or POST, where should this logic be implemented?

  • In the destroy() method
  • In the doFilter() method
  • In the init() method
  • In the service() method
The logic for different actions based on HTTP GET or POST requests should be implemented in the doFilter() method of the filter. This method is responsible for processing the request and can be customized for different scenarios.

The __________ method is called by the web container to indicate to a filter that it is being taken out of service.

  • close()
  • destroy()
  • release()
  • terminate()
The destroy() method is called by the web container to indicate to a filter that it is being taken out of service.

Filters are configured in the __________ file of a web application.

  • filter-config.xml
  • filter.xml
  • web-config.xml
  • web.xml
Filters are configured in the web.xml file of a web application.

The method __________ is used to handle request and response objects in a filter.

  • doFilter()
  • filterRequest()
  • initFilter()
  • processFilter()
The method doFilter() is used to handle request and response objects in a filter.

The filter's __________ method is invoked for every request/response pair processed by the filter.

  • doFilter()
  • doProcessing()
  • execute()
  • process()
The filter's doFilter() method is invoked for every request/response pair processed by the filter.

The __________ method of the FilterChain interface is used to invoke the next filter in the chain.

  • doFilter()
  • invokeNext()
  • nextFilter()
  • proceed()
The doFilter() method of the FilterChain interface is used to invoke the next filter in the chain.

When implementing a filter, it's critical to maintain the correct order of processing by calling __________ in the doFilter method.

  • doProcessing.filter()
  • filterChain.doFilter()
  • filterOrder.doFilter()
  • servletRequest.process()
In the doFilter method of a filter, it's important to call filterChain.doFilter() to ensure the correct order of processing continues.

In the filter chain, the __________ method is used to perform the actual filtering.

  • doFilter()
  • filterRequest()
  • initFilter()
  • processFilter()
In the filter chain, the doFilter() method is used to perform the actual filtering of requests and responses.