Class ResourceExistsSelector

  extended byorg.apache.cocoon.util.AbstractLogEnabled
      extended byorg.apache.cocoon.selection.ResourceExistsSelector
All Implemented Interfaces:
Disposable, org.apache.cocoon.selection.Selector, Serviceable, ThreadSafe

public class ResourceExistsSelector
extends org.apache.cocoon.util.AbstractLogEnabled
implements ThreadSafe, Serviceable, Disposable, org.apache.cocoon.selection.Selector

Selects the first of a set of Resources (usually files) that exists.

A parameter 'prefix',

   <map:parameter src="prefix" value="some/path"/<
may be supplied to the selector instance. This prefix is prepended to all test expressions before evaluation. The default prefix is '' (empty string), meaning that all expressions are relative to the current sitemap, unless explicitly overridden.

NOTE: Provided resource URI is resolved as Source, relative to the current sitemap, which differs from behavior of selector in previous versions. To resolve resource paths relative to the context root, provide prefix parameter:

   <map:parameter name="prefix" value="context://"/<

For example, we could define a ResourceExistsSelector with:

 <map:selector name="resource-exists"
               src="org.apache.cocoon.selection.ResourceExistsSelector" /<
And use it to build a PDF from XSL:FO or a higher-level XML format with:
  <map:match pattern="**.pdf"<
    <map:select type="resource-exists"<
       <map:when test="context/xdocs/{1}.fo"<
          <map:generate src="content/xdocs/{1}.fo" /<
         <map:generate src="content/xdocs/{1}.xml" /<
         <map:transform src="stylesheets/document2fo.xsl" /<
    <map:serialize type="fo2pdf" /<

$Id: ResourceExistsSelector.html 1304280 2012-03-23 11:18:01Z ilgrosso $

Field Summary
Fields inherited from interface org.apache.cocoon.selection.Selector
Constructor Summary
Method Summary
 void dispose()
 boolean select(String expression, Map objectModel, Parameters parameters)
 void service(ServiceManager manager)
Methods inherited from class org.apache.cocoon.util.AbstractLogEnabled
getLogger, setLogger
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail


public ResourceExistsSelector()
Method Detail


public void service(ServiceManager manager)
             throws ServiceException
Specified by:
service in interface Serviceable


public void dispose()
Specified by:
dispose in interface Disposable


public boolean select(String expression,
                      Map objectModel,
                      Parameters parameters)
Specified by:
select in interface org.apache.cocoon.selection.Selector

Copyright 1999-2008 The Apache Software Foundation. All Rights Reserved.