org.springframework.web.filter
Class GenericFilterBean

java.lang.Object
  org.springframework.web.filter.GenericFilterBean

All Implemented Interfaces:

Filter

Direct Known Subclasses:

DelegatingFilterProxy, OncePerRequestFilter

public abstract class GenericFilterBean
extends Object
implements Filter

Simple base implementation of javax.servlet.Filter that treats its config parameters as bean properties. Unknown parameters are ignored. A very handy superclass for any type of filter. Type conversion is automatic. It is also possible for subclasses to specify required properties.

This filter leaves actual filtering to subclasses, which have to implement Filter's doFilter method.

This filter superclass has no dependency on a Spring application context. Filters usually don't load their own context but rather access beans from the root application context, accessible via the ServletContext.

Since:

06.12.2003

Author:

Juergen Hoeller

See Also:

addRequiredProperty(java.lang.String), initFilterBean(), Filter.doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain), WebApplicationContextUtils.getWebApplicationContext(javax.servlet.ServletContext)

Field Summary

protected Log

logger Logger available to subclasses

Constructor Summary

GenericFilterBean()

Method Summary

protected void	addRequiredProperty(String property) Subclasses can invoke this method to specify that this property (which must match a JavaBean property they expose) is mandatory, and must be supplied as a config parameter.
void	destroy() Subclasses may override this to perform custom filter shutdown.
FilterConfig	getFilterConfig() Make the FilterConfig of this filter available.
protected String	getFilterName() Make the name of this filter available to subclasses.
protected ServletContext	getServletContext() Make the ServletContext of this filter available to subclasses.
void	init(FilterConfig filterConfig) Map config parameters onto bean properties of this filter, and invoke subclass initialization.
protected void	initBeanWrapper(BeanWrapper bw) Initialize the BeanWrapper for this GenericFilterBean, possibly with custom editors.
protected void	initFilterBean() Subclasses may override this to perform custom initialization.
void	setFilterConfig(FilterConfig filterConfig) Alternative way of initializing this filter.

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

logger

protected final Log logger

Logger available to subclasses

Constructor Detail

GenericFilterBean

public GenericFilterBean()

Method Detail

addRequiredProperty

protected final void addRequiredProperty(String property)

Subclasses can invoke this method to specify that this property (which must match a JavaBean property they expose) is mandatory, and must be supplied as a config parameter. This should be called from the constructor of a subclass

Parameters:

property - name of the required property

setFilterConfig

public final void setFilterConfig(FilterConfig filterConfig)

Alternative way of initializing this filter. Used by Servlet Filter version that shipped with WebLogic 6.1.

Parameters:

filterConfig - the configuration for this filter

Throws:

FatalBeanException - wrapping a ServletException thrown by the init method

See Also:

init(javax.servlet.FilterConfig)

init

public final void init(FilterConfig filterConfig)
                throws ServletException

Map config parameters onto bean properties of this filter, and invoke subclass initialization.

Specified by:

init in interface Filter

Parameters:

filterConfig - the configuration for this filter

Throws:

ServletException - if bean properties are invalid (or required properties are missing), or if subclass initialization fails.

See Also:

initFilterBean()

initBeanWrapper

protected void initBeanWrapper(BeanWrapper bw)
                        throws BeansException

Initialize the BeanWrapper for this GenericFilterBean, possibly with custom editors.

Parameters:

bw - the BeanWrapper to initialize

Throws:

BeansException - if thrown by BeanWrapper methods

See Also:

BeanWrapper.registerCustomEditor(java.lang.Class, java.beans.PropertyEditor)

getFilterConfig

public final FilterConfig getFilterConfig()

Make the FilterConfig of this filter available. Analogous to GenericServlet's getServletConfig.

Public to resemble the getFilterConfig method of the Servlet Filter version that shipped with WebLogic 6.1.

See Also:

GenericServlet.getServletConfig()

getFilterName

protected final String getFilterName()

Make the name of this filter available to subclasses. Analogous to GenericServlet's getServletName.

See Also:

GenericServlet.getServletName()

getServletContext

protected final ServletContext getServletContext()

Make the ServletContext of this filter available to subclasses. Analogous to GenericServlet's getServletContext.

See Also:

GenericServlet.getServletContext()

initFilterBean

protected void initFilterBean()
                       throws ServletException

Subclasses may override this to perform custom initialization. All bean properties of this filter will have been set before this method is invoked. This default implementation does nothing.

Throws:

ServletException - if subclass initialization fails

destroy

public void destroy()

Subclasses may override this to perform custom filter shutdown. This default implementation does nothing.

Specified by:

destroy in interface Filter