package org.apache.velocity.runtime.resource.loader;
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
import java.io.InputStream;
import java.util.Hashtable;
import java.util.Vector;
import java.util.Map;
import java.util.HashMap;
import org.apache.velocity.util.StringUtils;
import org.apache.velocity.runtime.resource.Resource;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.commons.collections.ExtendedProperties;
/**
* <p>
* ResourceLoader to load templates from multiple Jar files.
* </p>
* <p>
* The configuration of the JarResourceLoader is straightforward -
* You simply add the JarResourceLoader to the configuration via
* </p>
* <p><pre>
* resource.loader = jar
* jar.resource.loader.class = org.apache.velocity.runtime.resource.loader.JarResourceLoader
* jar.resource.loader.path = list of JAR <URL>s
* </pre></p>
*
* <p> So for example, if you had a jar file on your local filesystem, you could simply do
* <pre>
* jar.resource.loader.path = jar:file:/opt/myfiles/jar1.jar
* </pre>
* </p>
* <p> Note that jar specification for the <code>.path</code> configuration property
* conforms to the same rules for the java.net.JarUrlConnection class.
* </p>
*
* <p> For a working example, see the unit test case,
* org.apache.velocity.test.MultiLoaderTestCase class
* </p>
*
* @author <a href="mailto:[email protected]">Aki Nieminen</a>
* @author <a href="mailto:[email protected]">Dave Bryson</a>
* @version $Id: JarResourceLoader.java 691884 2008-09-04 06:46:51Z nbubna $
*/
public class JarResourceLoader extends ResourceLoader
{
/**
* Maps entries to the parent JAR File
* Key = the entry *excluding* plain directories
* Value = the JAR URL
*/
private Map entryDirectory = new HashMap(559);
/**
* Maps JAR URLs to the actual JAR
* Key = the JAR URL
* Value = the JAR
*/
private Map jarfiles = new HashMap(89);
/**
* Called by Velocity to initialize the loader
* @param configuration
*/
public void init( ExtendedProperties configuration)
{
log.trace("JarResourceLoader : initialization starting.");
// rest of Velocity engine still use legacy Vector
// and Hashtable classes. Classes are implicitly
// synchronized even if we don't need it.
Vector paths = configuration.getVector("path");
StringUtils.trimStrings(paths);
/*
* support the old version but deprecate with a log message
*/
if( paths == null || paths.size() == 0)
{
paths = configuration.getVector("resource.path");
StringUtils.trimStrings(paths);
if (paths != null && paths.size() > 0)
{
log.debug("JarResourceLoader : you are using a deprecated configuration"
+ " property for the JarResourceLoader -> '<name>.resource.loader.resource.path'."
+ " Please change to the conventional '<name>.resource.loader.path'.");
}
}
if (paths != null)
{
log.debug("JarResourceLoader # of paths : " + paths.size() );
for ( int i=0; i<paths.size(); i++ )
{
loadJar( (String)paths.get(i) );
}
}
log.trace("JarResourceLoader : initialization complete.");
}
private void loadJar( String path )
{
if (log.isDebugEnabled())
{
log.debug("JarResourceLoader : trying to load \"" + path + "\"");
}
// Check path information
if ( path == null )
{
String msg = "JarResourceLoader : can not load JAR - JAR path is null";
log.error(msg);
throw new RuntimeException(msg);
}
if ( !path.startsWith("jar:") )
{
String msg = "JarResourceLoader : JAR path must start with jar: -> see java.net.JarURLConnection for information";
log.error(msg);
throw new RuntimeException(msg);
}
if ( path.indexOf("!/") < 0 )
{
path += "!/";
}
// Close the jar if it's already open
// this is useful for a reload
closeJar( path );
// Create a new JarHolder
JarHolder temp = new JarHolder( rsvc, path );
// Add it's entries to the entryCollection
addEntries( temp.getEntries() );
// Add it to the Jar table
jarfiles.put( temp.getUrlPath(), temp );
}
/**
* Closes a Jar file and set its URLConnection
* to null.
*/
private void closeJar( String path )
{
if ( jarfiles.containsKey(path) )
{
JarHolder theJar = (JarHolder)jarfiles.get(path);
theJar.close();
}
}
/**
* Copy all the entries into the entryDirectory
* It will overwrite any duplicate keys.
*/
private void addEntries( Hashtable entries )
{
entryDirectory.putAll( entries );
}
/**
* Get an InputStream so that the Runtime can build a
* template with it.
*
* @param source name of template to get
* @return InputStream containing the template
* @throws ResourceNotFoundException if template not found
* in the file template path.
*/
public InputStream getResourceStream( String source )
throws ResourceNotFoundException
{
InputStream results = null;
if (org.apache.commons.lang.StringUtils.isEmpty(source))
{
throw new ResourceNotFoundException("Need to have a resource!");
}
String normalizedPath = StringUtils.normalizePath( source );
if ( normalizedPath == null || normalizedPath.length() == 0 )
{
String msg = "JAR resource error : argument " + normalizedPath +
" contains .. and may be trying to access " +
"content outside of template root. Rejected.";
log.error( "JarResourceLoader : " + msg );
throw new ResourceNotFoundException ( msg );
}
/*
* if a / leads off, then just nip that :)
*/
if ( normalizedPath.startsWith("/") )
{
normalizedPath = normalizedPath.substring(1);
}
if ( entryDirectory.containsKey( normalizedPath ) )
{
String jarurl = (String)entryDirectory.get( normalizedPath );
if ( jarfiles.containsKey( jarurl ) )
{
JarHolder holder = (JarHolder)jarfiles.get( jarurl );
results = holder.getResource( normalizedPath );
return results;
}
}
throw new ResourceNotFoundException( "JarResourceLoader Error: cannot find resource " +
source );
}
// TODO: SHOULD BE DELEGATED TO THE JARHOLDER
/**
* @see org.apache.velocity.runtime.resource.loader.ResourceLoader#isSourceModified(org.apache.velocity.runtime.resource.Resource)
*/
public boolean isSourceModified(Resource resource)
{
return true;
}
/**
* @see org.apache.velocity.runtime.resource.loader.ResourceLoader#getLastModified(org.apache.velocity.runtime.resource.Resource)
*/
public long getLastModified(Resource resource)
{
return 0;
}
}
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