- All Implemented Interfaces:
- David Becker
- See Also:
Field SummaryModifier and TypeFieldDescription
protected booleanAllow exec (normally blocked for security)
protected Patternregex pattern to match when evaluating content types
protected intDebug level for this servlet.
protected LongExpiration time in seconds for the doc.
protected booleanvirtual path can be webapp-relative
protected final Patterndefault pattern for ssi filter content type matching
Method SummaryModifier and TypeMethodDescription
destroy()Called by the web container to indicate to a filter that it is being taken out of service.
doFiltermethod of the Filter is called by the container each time a request/response pair is passed through the chain due to a client request for a resource at the end of the chain.
voidCalled by the web container to indicate to a filter that it is being placed into service.
configprotected FilterConfig config
debugprotected int debugDebug level for this servlet.
expiresprotected Long expiresExpiration time in seconds for the doc.
isVirtualWebappRelativeprotected boolean isVirtualWebappRelativevirtual path can be webapp-relative
contentTypeRegExprotected Pattern contentTypeRegExregex pattern to match when evaluating content types
shtmlRegExprotected final Pattern shtmlRegExdefault pattern for ssi filter content type matching
allowExecprotected boolean allowExecAllow exec (normally blocked for security)
initCalled by the web container to indicate to a filter that it is being placed into service. The servlet container calls the init method exactly once after instantiating the filter. The init method must complete successfully before the filter is asked to do any filtering work.
The web container cannot place the filter into service if the init method either:
- Throws a ServletException
- Does not return within a time period defined by the web container
doFilterpublic void doFilter
(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletExceptionThe
doFiltermethod of the Filter is called by the container each time a request/response pair is passed through the chain due to a client request for a resource at the end of the chain. The FilterChain passed in to this method allows the Filter to pass on the request and response to the next entity in the chain.
A typical implementation of this method would follow the following pattern:-
1. Examine the request
2. Optionally wrap the request object with a custom implementation to filter content or headers for input filtering
3. Optionally wrap the response object with a custom implementation to filter content or headers for output filtering
4. a) Either invoke the next entity in the chain using the FilterChain object (
4. b) or not pass on the request/response pair to the next entity in the filter chain to block the request processing
5. Directly set headers on the response after invocation of the next entity in the filter chain.
- Specified by:
request- The request to process
response- The response associated with the request
chain- Provides access to the next filter in the chain for this filter to pass the request and response to for further processing
IOException- if an I/O error occurs during this filter's processing of the request
ServletException- if the processing fails for any other reason
destroypublic void destroy()Called by the web container to indicate to a filter that it is being taken out of service. This method is only called once all threads within the filter's doFilter method have exited or after a timeout period has passed. After the web container calls this method, it will not call the doFilter method again on this instance of the filter.
This method gives the filter an opportunity to clean up any resources that are being held (for example, memory, file handles, threads) and make sure that any persistent state is synchronized with the filter's current state in memory.