org.apache.catalina.valves

Class CrawlerSessionManagerValve

java.lang.Object

org.apache.catalina.valves.ValveBase

org.apache.catalina.valves.CrawlerSessionManagerValve

All Implemented Interfaces:

EventListener, MBeanRegistration, javax.servlet.http.HttpSessionBindingListener, Contained, Lifecycle, Valve

public class CrawlerSessionManagerValve
extends ValveBase
implements Lifecycle, javax.servlet.http.HttpSessionBindingListener

Web crawlers can trigger the creation of many thousands of sessions as they crawl a site which may result in significant memory consumption. This Valve ensures that crawlers are associated with a single session - just like normal users - regardless of whether or not they provide a session token with their requests.

Field Summary

Fields

Modifier and Type	Field and Description
protected LifecycleSupport	lifecycle The lifecycle event support for this component.
protected boolean	started

Fields inherited from class org.apache.catalina.valves.ValveBase

container, controller, domain, info, mserver, next, oname

Fields inherited from interface org.apache.catalina.Lifecycle

AFTER_START_EVENT, AFTER_STOP_EVENT, BEFORE_START_EVENT, BEFORE_STOP_EVENT, DESTROY_EVENT, INIT_EVENT, PERIODIC_EVENT, START_EVENT, STOP_EVENT

Constructor Summary

Constructors

Constructor and Description
CrawlerSessionManagerValve()

Method Summary

Modifier and Type	Method and Description
void	addLifecycleListener(LifecycleListener listener) Add a LifecycleEvent listener to this component.
LifecycleListener[]	findLifecycleListeners() Get the lifecycle listeners associated with this lifecycle.
Map<String,String>	getClientIpSessionId()
String	getCrawlerUserAgents()
int	getSessionInactiveInterval()
void	invoke(Request request, Response response) The implementation-specific logic represented by this Valve.
void	removeLifecycleListener(LifecycleListener listener) Remove a LifecycleEvent listener from this component.
void	setCrawlerUserAgents(String crawlerUserAgents) Specify the regular expression (using Pattern) that will be used to identify crawlers based in the User-Agent header provided.
void	setSessionInactiveInterval(int sessionInactiveInterval) Specify the session timeout (in seconds) for a crawler's session.
void	start() Prepare for the beginning of active use of the public methods of this component.
void	stop() Gracefully terminate the active use of the public methods of this component.
void	valueBound(javax.servlet.http.HttpSessionBindingEvent event)
void	valueUnbound(javax.servlet.http.HttpSessionBindingEvent event)

Methods inherited from class org.apache.catalina.valves.ValveBase

backgroundProcess, createObjectName, event, getContainer, getContainerName, getController, getDomain, getInfo, getNext, getObjectName, getParentName, postDeregister, postRegister, preDeregister, preRegister, setContainer, setController, setNext, setObjectName, toString

Methods inherited from class java.lang.Object

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

Field Detail

lifecycle

protected LifecycleSupport lifecycle

The lifecycle event support for this component.

started

protected boolean started

Constructor Detail

CrawlerSessionManagerValve

public CrawlerSessionManagerValve()

Method Detail

setCrawlerUserAgents

public void setCrawlerUserAgents(String crawlerUserAgents)

Specify the regular expression (using Pattern) that will be used to identify crawlers based in the User-Agent header provided. The default is ".*GoogleBot.*|.*bingbot.*|.*Yahoo! Slurp.*"

Parameters:

crawlerUserAgents - The regular expression using Pattern

getCrawlerUserAgents

public String getCrawlerUserAgents()

Returns:

The current regular expression being used to match user agents.

See Also:

setCrawlerUserAgents(String)

setSessionInactiveInterval

public void setSessionInactiveInterval(int sessionInactiveInterval)

Specify the session timeout (in seconds) for a crawler's session. This is typically lower than that for a user session. The default is 60 seconds.

Parameters:

sessionInactiveInterval - The new timeout for crawler sessions

getSessionInactiveInterval

public int getSessionInactiveInterval()

Returns:

The current timeout in seconds

See Also:

setSessionInactiveInterval(int)

getClientIpSessionId

public Map<String,String> getClientIpSessionId()

addLifecycleListener

public void addLifecycleListener(LifecycleListener listener)

Description copied from interface: Lifecycle

Add a LifecycleEvent listener to this component.

Specified by:

addLifecycleListener in interface Lifecycle

Parameters:

listener - The listener to add

findLifecycleListeners

public LifecycleListener[] findLifecycleListeners()

Description copied from interface: Lifecycle

Get the lifecycle listeners associated with this lifecycle. If this Lifecycle has no listeners registered, a zero-length array is returned.

Specified by:

findLifecycleListeners in interface Lifecycle

removeLifecycleListener

public void removeLifecycleListener(LifecycleListener listener)

Description copied from interface: Lifecycle

Remove a LifecycleEvent listener from this component.

Specified by:

removeLifecycleListener in interface Lifecycle

Parameters:

listener - The listener to remove

start

public void start()
           throws LifecycleException

Description copied from interface: Lifecycle

Prepare for the beginning of active use of the public methods of this component. This method should be called before any of the public methods of this component are utilized. It should also send a LifecycleEvent of type START_EVENT to any registered listeners.

Specified by:

start in interface Lifecycle

Throws:

LifecycleException - if this component detects a fatal error that prevents this component from being used

stop

public void stop()
          throws LifecycleException

Description copied from interface: Lifecycle

Gracefully terminate the active use of the public methods of this component. This method should be the last one called on a given instance of this component. It should also send a LifecycleEvent of type STOP_EVENT to any registered listeners.

Specified by:

stop in interface Lifecycle

Throws:

LifecycleException - if this component detects a fatal error that needs to be reported

invoke

public void invoke(Request request,
                   Response response)
            throws IOException,
                   javax.servlet.ServletException

Description copied from class: ValveBase

The implementation-specific logic represented by this Valve. See the Valve description for the normal design patterns for this method.

This method MUST be provided by a subclass.

Specified by:

invoke in interface Valve

Specified by:

invoke in class ValveBase

Parameters:

request - The servlet request to be processed

response - The servlet response to be created

Throws:

IOException - if an input/output error occurs

javax.servlet.ServletException - if a servlet error occurs

valueBound

public void valueBound(javax.servlet.http.HttpSessionBindingEvent event)

Specified by:

valueBound in interface javax.servlet.http.HttpSessionBindingListener

valueUnbound

public void valueUnbound(javax.servlet.http.HttpSessionBindingEvent event)

Specified by:

valueUnbound in interface javax.servlet.http.HttpSessionBindingListener