org.apache.cocoon.acting
Class ResourceExistsAction

java.lang.Object
  |
  +--org.apache.avalon.framework.logger.AbstractLoggable
        |
        +--org.apache.cocoon.acting.AbstractAction
              |
              +--org.apache.cocoon.acting.ComposerAction
                    |
                    +--org.apache.cocoon.acting.ResourceExistsAction

All Implemented Interfaces:

Action, org.apache.avalon.framework.component.Component, org.apache.avalon.framework.component.Composable, org.apache.avalon.framework.logger.Loggable, org.apache.avalon.framework.thread.ThreadSafe

public class ResourceExistsAction

extends ComposerAction

implements org.apache.avalon.framework.thread.ThreadSafe

This action simply checks to see if a given resource exists. It checks whether the specified in the src attribute source exists or not. The action returns empty Map if it exists, null otherwise.

Instead of src attribute, source can be specified using parameter named 'url' (this is old syntax).

Version:

CVS $Id: ResourceExistsAction.java,v 1.5.2.1 2002/10/22 01:52:23 vgritsenko Exp $

Author:

Donald Ball

Fields inherited from class org.apache.cocoon.acting.ComposerAction

manager

Fields inherited from class org.apache.cocoon.acting.AbstractAction

EMPTY_MAP

Fields inherited from interface org.apache.cocoon.acting.Action

ROLE

Constructor Summary

ResourceExistsAction()

Method Summary

java.util.Map

act(Redirector redirector, SourceResolver resolver, java.util.Map objectModel, java.lang.String source, org.apache.avalon.framework.parameters.Parameters parameters) Controls the processing against some values of the Dictionary objectModel and returns a Map object with values used in subsequent sitemap substitution patterns.

Methods inherited from class org.apache.cocoon.acting.ComposerAction

compose

Methods inherited from class org.apache.avalon.framework.logger.AbstractLoggable

getLogger, setLogger, setupLogger, setupLogger, setupLogger

Methods inherited from class java.lang.Object

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

Constructor Detail

ResourceExistsAction

public ResourceExistsAction()

Method Detail

act

public java.util.Map act(Redirector redirector,
                         SourceResolver resolver,
                         java.util.Map objectModel,
                         java.lang.String source,
                         org.apache.avalon.framework.parameters.Parameters parameters)
                  throws java.lang.Exception

Description copied from interface: Action

Controls the processing against some values of the Dictionary objectModel and returns a Map object with values used in subsequent sitemap substitution patterns. NOTE: This interface is designed so that implentations can be ThreadSafe. When an action is ThreadSafe, only one instance serves all requests : this reduces memory usage and avoids pooling.

Following copied from interface: org.apache.cocoon.acting.Action

Parameters:

resolver - The SourceResolver in charge

objectModel - The Map with object of the calling environment which can be used to select values this controller may need (ie Request, Response).

source - A source String to the Action

parameters - The Parameters for this invocation

Returns:

Map The returned Map object with sitemap substitution values which can be used in subsequent elements attributes like src= using a xpath like expression: src="mydir/{myval}/foo" If the return value is null the processing inside the element of the sitemap will be skipped.

Throws:

java.lang.Exception - Indicates something is totally wrong