org.beangle.commons.web.filter

Class GenericHttpFilter

java.lang.Object

org.beangle.commons.web.filter.GenericHttpFilter

All Implemented Interfaces:

javax.servlet.Filter, Disposable, Initializing

Direct Known Subclasses:

DelegatingFilterProxy, GenericCompositeFilter, OncePerRequestFilter

public abstract class GenericHttpFilter
extends Object
implements javax.servlet.Filter, Initializing, Disposable

Version:

$Id: GenericHttpFilter.java Nov 20, 2010 7:12:16 PM chaostone $

Author:

chaostone

Field Summary

Fields

Modifier and Type	Field and Description
protected org.slf4j.Logger	logger Logger available to subclasses

Constructor Summary

Constructors

Constructor and Description
GenericHttpFilter()

Method Summary

Modifier and Type	Method and Description
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.
javax.servlet.FilterConfig	getFilterConfig() Make the FilterConfig of this filter available, if any.
protected String	getFilterName() Make the name of this filter available to subclasses.
protected javax.servlet.ServletContext	getServletContext() Make the ServletContext of this filter available to subclasses.
void	init() Calls the initFilterBean() method that might contain custom initialization of a subclass.
void	init(javax.servlet.FilterConfig filterConfig) Standard way of initializing this filter.
protected void	initFilterBean() Subclasses may override this to perform custom initialization.
protected void	initParams(javax.servlet.FilterConfig config)

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 org.slf4j.Logger logger

Logger available to subclasses

Constructor Detail

GenericHttpFilter

public GenericHttpFilter()

Method Detail

init

public void init()
          throws Exception

Calls the initFilterBean() method that might contain custom initialization of a subclass.

Only relevant in case of initialization as bean, where the standard init(FilterConfig) method won't be called.

Specified by:

init in interface Initializing

Throws:

Exception

See Also:

initFilterBean(), init(javax.servlet.FilterConfig)

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.

This method is only relevant in case of traditional initialization driven by a FilterConfig instance.

Parameters:

property - name of the required property

init

public final void init(javax.servlet.FilterConfig filterConfig)
                throws javax.servlet.ServletException

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

Specified by:

init in interface javax.servlet.Filter

Parameters:

filterConfig - the configuration for this filter

Throws:

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

See Also:

initFilterBean()

initParams

protected void initParams(javax.servlet.FilterConfig config)
                   throws javax.servlet.ServletException

Throws:

javax.servlet.ServletException

getFilterConfig

public final javax.servlet.FilterConfig getFilterConfig()

Make the FilterConfig of this filter available, if any. Analogous to GenericServlet's getServletConfig().

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

Returns:

the FilterConfig instance, or null if none available

See Also:

GenericServlet.getServletConfig()

getFilterName

protected final String getFilterName()

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

Takes the FilterConfig's filter name by default. If initialized as bean in application context, it falls back to the bean name as defined in the bean factory.

Returns:

the filter name, or null if none available

See Also:

GenericServlet.getServletName(), FilterConfig.getFilterName()

getServletContext

protected final javax.servlet.ServletContext getServletContext()

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

Takes the FilterConfig's ServletContext by default. If initialized as bean in application context, it falls back to the ServletContext that the bean factory runs in.

Returns:

the ServletContext instance, or null if none available

See Also:

GenericServlet.getServletContext(), FilterConfig.getServletContext()

initFilterBean

protected void initFilterBean()
                       throws javax.servlet.ServletException

Subclasses may override this to perform custom initialization. All bean properties of this filter will have been set before this method is invoked.

Note: This method will be called from standard filter initialization as well as filter bean initialization in a application context. Filter name and ServletContext will be available in both cases.

This default implementation is empty.

Throws:

javax.servlet.ServletException - if subclass initialization fails

See Also:

getFilterName(), getServletContext()

destroy

public void destroy()

Subclasses may override this to perform custom filter shutdown.

Note: This method will be called from standard filter destruction as well as filter bean destruction in a application context.

This default implementation is empty.

Specified by:

destroy in interface javax.servlet.Filter

Specified by:

destroy in interface Disposable