Name
Filter
Synopsis
A filter processes a request on either side of the target content. If
a web application is configured to filter requests aimed at particular
targets (either servlets or paths), the server will instead call the
doFilter()
method of the first
Filter
installed for that resource. A
FilterChain
object passed to the
doFilter()
method can be used by the filter to call
the next filter in the sequence, or to invoke the target resource if all
filters have been processed. When the doFilter()
method
finishes executing, control is ceded back to the web server or the preceding
filter.
The Filter
interface also provides an
init()
method which will be called and allowed finish
execution before any doFilter()
methods are called.
public interface Filter { // Public Instance Methods public abstract void destroy(); public abstract void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOExceptionServletException; public abstract void init( FilterConfig filterConfig) throws ServletException; }
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