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<?xml version="1.0"?>
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<!DOCTYPE document [
<!ENTITY project SYSTEM "project.xml">
]>
<document url="resources.html">
&project;
<properties>
<author email="remm@apache.org">Remy Maucherat</author>
<title>The Resources Component</title>
</properties>
<body>
<section name="Introduction">
<p>The <strong>Resources</strong> element represents the <em>web
application static resources</em>, from which classes will be loaded,
HTML, JSP and the other static files will be served. This allows the webapp
to reside on various mediums other than the filesystem, like compressed
in a WAR file, in a JDBC database, or in a more advanced versioning
repository.</p>
<p>A unified caching engine is provided for all accesses to the webapp
resources made by the servlet container and web applications which use the
container provided mechanisms to access such resources, such as class laoder
access, access through the <code>ServletContext</code> interface, or native
access through the <code>DirectoryContext</code> interface.</p>
<p><strong>Note: Running a webapp with non-filesystem based
Resources implementations is only possible when the webapp does not
rely on direct filesystem access to its own resources, and uses the methods
in the ServletContext interface to access them.</strong></p>
<p>A Resources element MAY be nested inside a
<a href="context.html">Context</a> component. If it is not included,
a default filesystem based Resources will be created automatically,
which is sufficient for most requirements.</p>
</section>
<section name="Attributes">
<subsection name="Common Attributes">
<p>All implementations of <strong>Resources</strong>
support the following attributes:</p>
<attributes>
<attribute name="className" required="false">
<p>Java class name of the implementation to use. This class must
implement the <code>javax.naming.directory.DirContext</code> interface.
It is recommended for optimal functionality and performance,
but not mandatory, that the class extend
<code>org.apache.naming.resources.BaseDirContext</code>, as well as
use the special object types provided in the
<code>org.apache.naming.resources</code> for returned objects.
If not specified, the standard value (defined below) will be used.</p>
</attribute>
</attributes>
</subsection>
<subsection name="Standard Implementation">
<p>The standard implementation of <strong>Resources</strong> is
<strong>org.apache.naming.resources.FileDirContext</strong>, and
is configured by its parent Context element.</p>
</subsection>
</section>
<section name="Nested Components">
<p>No components may be nested inside a <strong>Resources</strong> element.</p>
</section>
<section name="Special Features">
<p>No special features are associated with a <strong>Resources</strong>
element.</p>
</section>
</body>
</document>