org.apache.catalina.filters
Class FilterBase

java.lang.Object
  org.apache.catalina.filters.FilterBase

All Implemented Interfaces:

Filter

Direct Known Subclasses:

AddDefaultCharsetFilter, CsrfPreventionFilter, ExpiresFilter, RequestFilter

public abstract class FilterBase
extends Object
implements Filter

Base class for filters that provides generic initialisation and a simple no-op destruction.

Author:

xxd

Field Summary

protected static StringManager

sm

Constructor Summary

FilterBase()

Method Summary

void	destroy() Called by the web container to indicate to a filter that it is being taken out of service.
protected abstract Log	getLogger()
void	init(FilterConfig filterConfig) Called by the web container to indicate to a filter that it is being placed into service.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface javax.servlet.Filter

doFilter

Field Detail

sm

protected static final StringManager sm

Constructor Detail

FilterBase

public FilterBase()

Method Detail

getLogger

protected abstract Log getLogger()

init

public void init(FilterConfig filterConfig)
          throws ServletException

Description copied from interface: javax.servlet.Filter

Called 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
1.Throws a ServletException
2.Does not return within a time period defined by the web container

Specified by:

init in interface Filter

Throws:

ServletException

destroy

public void destroy()

Description copied from interface: javax.servlet.Filter

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.

Specified by:

destroy in interface Filter