org.pageseeder.flint.Index Maven / Gradle / Ivy
/*
* Copyright 2015 Allette Systems (Australia)
* http://www.allette.com.au
*
* Licensed 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.pageseeder.flint;
import java.net.URI;
import java.util.Collection;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import javax.xml.transform.Templates;
import javax.xml.transform.TransformerException;
import org.pageseeder.flint.content.Content;
import org.pageseeder.flint.content.ContentType;
import org.pageseeder.flint.indexing.FlintField;
import org.pageseeder.flint.templates.TemplatesCache;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Provides the details needed to build the data to index from the original content.
*
* The path to a valid XSLT script is needed and parameters can be provided as well.
*
*
The XSLT script should produce valid IndexXML format (see DTD).
*
* @author Jean-Baptiste Reure
* @version 26 February 2010
*/
public abstract class Index {
/**
* Logger to use for this config object.
*/
private static final Logger LOGGER = LoggerFactory.getLogger(Index.class);
private final String _id;
private final String _catalog;
/**
* The XSLT script.
*/
private final Map _templates = new ConcurrentHashMap<>();
public Index(String id) {
this(id, null);
}
public Index(String id, String catalog) {
this._id = id;
this._catalog = catalog;
IndexManager.registerIndex(this);
}
public String getCatalog() {
return this._catalog;
}
/**
* Return the unique identifier for this index.
*
* @return The Index ID.
*/
public final String getIndexID() {
return this._id;
}
public void close() {
IndexIO io = getIndexIO();
if (io != null) {
try {
io.stop();
} catch (Exception ex) {
LOGGER.error("Failed to stop IndexIO for {}", this._id, ex);
}
}
IndexManager.deregisterIndex(this);
}
public abstract IndexIO getIndexIO();
// Fields management =========================================================================
/**
* Used to define lucene fields specific to a content (should be overwritten by subclasses).
* Can be used to ensure that certain fields are always in the index.
*
* @param content the actual content
*
* @return the list of fields, null if none
*/
public Collection getFields(Content content) {
return null;
}
// Parameters management =========================================================================
/**
* Used to define parameters specific to a content (should be overwritten by subclasses).
*
* @param content the actual content
*
* @return the map of parameters, null if none
*/
public Map getParameters(Content content) {
return null;
}
// Templates management =========================================================================
/**
* Returns the compiled XSLT templates, null if there are no templates associated with
* this content type and media type.
*
* @param type the type of content to index.
* @param media the media type of the content (eg. "application/xml")
*
* @return the compiled XSLT templates; null if not found.
*/
public Templates getTemplates(ContentType type, String media) {
ContentDefinition def = new ContentDefinition(type, media);
// LOGGER.debug("Retrieving templates for {}", def);
URI uri = this._templates.get(def);
try {
return uri == null ? null : TemplatesCache.get(uri);
} catch (TransformerException ex) {
return null;
}
}
/**
* Sets the XSLT templates to use for the specified content type, media type.
*
* @param type the type of content to index.
* @param media the media type of the content (eg. "application/xml").
* @param template the full path to the XSLT template file.
*
* @throws TransformerException If the templates are invalid.
*/
public void setTemplates(ContentType type, String media, URI template) throws TransformerException {
// load it in the cache to validate it
TemplatesCache.get(template);
// ok store it then
ContentDefinition def = new ContentDefinition(type, media);
LOGGER.debug("Adding templates for {}", def);
this._templates.put(def, template);
}
/**
* Remove the template linked to the content type/media specified
*
* @param type the content type
* @param media the content media type
*/
public void removeTemplate(ContentType type, String media) {
ContentDefinition def = new ContentDefinition(type, media);
this._templates.remove(def);
}
/**
* Clear all templates.
*/
public void clearTemplates() {
this._templates.clear();
}
// Private helpers ==============================================================================
/**
* A simple immutable object to use as a key and optimised for fast retrieval.
*
* @author Jean-Baptiste Reure
* @author Christophe Lauret
* @version 29 July 2010
*/
private static final class ContentDefinition {
/** Content type */
private final ContentType _type;
/** Media Type */
private final String _media;
/** Pre-computed hash code for this object */
private final int hashCode;
/**
* Creates a new content definition.
*
* @param type The content type
* @param media The media type
*/
public ContentDefinition(ContentType type, String media) {
this._type = type;
this._media = media;
this.hashCode = hashCode(type, media);
}
/**
* {@inheritDoc}
*/
@Override
public boolean equals(Object o) {
if (!(o instanceof ContentDefinition)) return false;
return this.equalsDefinition((ContentDefinition)o);
}
/**
* Compares two content definition for equality.
*
* @param def the content definition to compare for equality.
* @return true if the type, media and config ID are equal;
* false otherwise.
*/
public boolean equalsDefinition(ContentDefinition def) {
if (def == null) return false;
if (this == def) return true;
if (!this._type.equals(def._type)) return false;
return (this._media == null && def._media == null) || (this._media != null && this._media.equals(def._media));
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
return this.hashCode;
}
/**
* {@inheritDoc}
*/
@Override
public String toString() {
return this._type.toString() + "|" + this._media;
}
/**
* Computes the hash code to make a more efficient key.
*
* @param type The content type
* @param media The media type
*
* @return the hashcode for this object.
*/
private static int hashCode(ContentType type, String media) {
return type.hashCode() * 13 + (media == null ? 0 : (media.hashCode() * 19));
}
}
}