/*
* 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.
*/
package org.apache.cocoon.generation;
import org.apache.avalon.framework.activity.Initializable;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.ResourceNotFoundException;
import org.apache.cocoon.caching.CacheableProcessingComponent;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.util.Deprecation;
import org.apache.excalibur.source.SourceValidity;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
import org.xmldb.api.DatabaseManager;
import org.xmldb.api.base.Collection;
import org.xmldb.api.base.Database;
import org.xmldb.api.base.XMLDBException;
import java.io.IOException;
import java.util.Map;
/**
* This class implements generation of a XML:DB collection
* contents as a directory listing.
*
* <pre>
* <driver>
* (a valid DB:XML compliant driver)
* </driver>
* <base>
* xmldb:yourdriver://host/an/optional/path/to/be/prepended
* </base>
* </pre>
*
* NOTE: the driver can be any DB:XML compliant driver (although this
* component has been tested only with
* <a href="http://www.dbxml.org">dbXML</a>, and the trailing
* slash in the base tag is important!
*
* @author <a href="mailto:gianugo@rabellino.it">Gianugo Rabellino</a>
* @version CVS $Id$
* @deprecated Use the XML:DB pseudo protocol instead.
*/
public class XMLDBCollectionGenerator extends ServiceableGenerator
implements CacheableProcessingComponent, Configurable, Initializable {
protected static final String URI =
"http://apache.org/cocoon/xmldb/1.0";
protected static final String PREFIX = "collection";
protected static final String RESOURCE_COUNT_ATTR = "resources";
protected static final String COLLECTION_COUNT_ATTR = "collections";
protected static final String COLLECTION = "collection";
protected static final String QCOLLECTION = PREFIX + ":collection";
protected static final String RESOURCE = "resource";
protected static final String QRESOURCE = PREFIX + ":resource";
protected String driver;
protected String base;
protected String col;
protected Database database;
protected Collection collection;
protected final AttributesImpl attributes = new AttributesImpl();
/**
* Recycle the component, keep only the configuration variables
* and the database instance for reuse.
*/
public void recycle() {
super.recycle();
this.col = null;
this.collection = null;
}
/**
* Configure the component. This class is expecting a configuration
* like the following one:
* <pre>
* <driver>org.dbxml.client.xmldb.DatabaseImpl</driver>
* <base>xmldb:dbxml:///db/</base>
* </pre>
* NOTE: the driver can be any DB:XML compliant driver (although this
* component has been tested only with
* <a href="http://www.dbxml.org">dbXML</a>, and the trailing
* slash in the base tag is important!
*
* @exception ConfigurationException (configuration invalid or missing)
*/
public void configure(Configuration conf) throws ConfigurationException {
this.driver = conf.getChild("driver").getValue();
this.base = conf.getChild("base").getValue();
}
/**
* Initialize the component getting a database instance.
*
* @exception Exception if an error occurs
*/
public void initialize() throws Exception {
try {
Class c = Class.forName(driver);
database = (Database)c.newInstance();
DatabaseManager.registerDatabase(database);
} catch (XMLDBException xde) {
getLogger().error("Unable to connect to the XML:DB database");
throw new ProcessingException("Unable to connect to the XML DB"
+ xde.getMessage());
} catch (Exception e) {
getLogger().error("There was a problem setting up the connection");
getLogger().error("Make sure that your driver is available");
throw new ProcessingException("Problem setting up the connection: "
+ e.getMessage());
}
}
public void setup(SourceResolver resolver,
Map objectModel,
String src,
Parameters par)
throws ProcessingException, SAXException,IOException {
Deprecation.logger.warn("The XMLDBCollectionGenerator is deprecated. Use the XML:DB pseudo protocol instead");
super.setup(resolver, objectModel, src, par);
}
/**
* The component isn't cached (yet)
*/
public SourceValidity getValidity() {
return null;
}
/**
* The component isn't cached (yet)
*/
public java.io.Serializable getKey() {
return null;
}
/**
* Parse the requested URI, connect to the XML:DB database
* and fetch the requested resource.
*
* @exception ProcessingException something unexpected happened with the DB
*/
public void generate()
throws IOException, SAXException, ProcessingException {
//String col = "/";
//if (source.indexOf('/') != -1)
col = source;
try {
collection = DatabaseManager.getCollection(base + col);
if (collection == null) {
throw new ResourceNotFoundException("Collection " + col +
" not found");
}
collectionToSAX(collection);
collection.close();
} catch (XMLDBException xde) {
throw new ProcessingException("Unable to fetch content '"
+ source + "':" + xde.getMessage());
} catch (NullPointerException npe) {
getLogger().error("The XML:DB driver raised an exception");
getLogger().error("probably the document was not found");
throw new ProcessingException("Null pointer exception while " +
"retrieving document : " + npe.getMessage());
}
}
/**
* Output SAX events listing the collection.
*
* @exception SAXException
*/
public void collectionToSAX(Collection collection)
throws SAXException {
String ncollections;
String nresources;
String[] resources;
String[] collections;
try {
ncollections = Integer.toString(collection.getChildCollectionCount());
nresources = Integer.toString(collection.getResourceCount());
attributes.clear();
attributes.addAttribute("", RESOURCE_COUNT_ATTR,
RESOURCE_COUNT_ATTR, "CDATA", nresources);
attributes.addAttribute("", COLLECTION_COUNT_ATTR,
COLLECTION_COUNT_ATTR, "CDATA", ncollections);
collections = collection.listChildCollections();
resources = collection.listResources();
this.xmlConsumer.startDocument();
this.xmlConsumer.startPrefixMapping(PREFIX, URI);
this.xmlConsumer.startElement(URI, "collections",
"collection:collections", attributes);
// Print child collections
for (int i = 0; i < collections.length; i++) {
attributes.clear();
attributes.addAttribute("", "name", "name", "CDATA", collections[i]);
this.xmlConsumer.startElement(URI, COLLECTION,
QCOLLECTION, attributes);
this.xmlConsumer.endElement(URI, COLLECTION, COLLECTION);
}
// Print child resources
for (int i = 0; i < resources.length; i++) {
attributes.clear();
attributes.addAttribute("", "name", "name", "CDATA", resources[i]);
this.xmlConsumer.startElement(URI, RESOURCE,
QRESOURCE, attributes);
this.xmlConsumer.endElement(URI, RESOURCE, RESOURCE);
}
this.xmlConsumer.endElement(URI, "collections",
"collection:collections");
this.xmlConsumer.endPrefixMapping(PREFIX);
this.xmlConsumer.endDocument();
} catch (XMLDBException xde) {
getLogger().warn("Collection listing failed: " + xde.getMessage());
throw new SAXException("Collection listing failed: " + xde.getMessage());
}
}
}