Which of the following statements are true?
Choose at least one answer.
A. A filter must extend the HttpFilter class Incorrect
B. A filter must implement the Filter interface Correct
C. Filters are chained to
servlets through the flter tag in the deployment descriptor Correct
D. A filter must be mapped to one and only one servlet Incorrect
E. A filter may be mapped either to a single servlet or to multiple servlets via a URL
pattern Correct
The answers are B, C, and E, but I don't agree with C. I believe the filters are chained to servlets through the "<filter-mapping>", not "<filter>" tag, because <filter> declares a filter, not saying anything about the associated servlet.
Am I being too picky or is the question wrong..? Thanks.
), filters are chained to other filters, and it is the final filter in the chain which then passes the request to either a servlet (including a JSP) or a static resource. It is the <filter-mapping> tag in the DD which declares a filter to be part of a filter chain for a matching request, and the order of the tags in the DD is synonymous with the order of the filters in the chain.