com.buddycloud.channeldirectory.search.ChannelDirectoryComponent.java Source code

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Here is the source code for com.buddycloud.channeldirectory.search.ChannelDirectoryComponent.java

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/*
 * Copyright 2011 buddycloud
 *
 * 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 com.buddycloud.channeldirectory.search;

import java.beans.PropertyVetoException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

import org.apache.log4j.Logger;
import org.dom4j.Element;
import org.dom4j.Namespace;
import org.xmpp.component.AbstractComponent;
import org.xmpp.packet.IQ;
import org.xmpp.packet.Packet;

import com.buddycloud.channeldirectory.commons.db.ChannelDirectoryDataSource;
import com.buddycloud.channeldirectory.search.handler.QueryHandler;
import com.buddycloud.channeldirectory.search.handler.active.MostActiveQueryHandler;
import com.buddycloud.channeldirectory.search.handler.common.mahout.ChannelRecommender;
import com.buddycloud.channeldirectory.search.handler.content.ContentQueryHandler;
import com.buddycloud.channeldirectory.search.handler.metadata.MetadataQueryHandler;
import com.buddycloud.channeldirectory.search.handler.nearby.NearbyQueryHandler;
import com.buddycloud.channeldirectory.search.handler.recommendation.RecommendationQueryHandler;
import com.buddycloud.channeldirectory.search.handler.similarity.SimilarityQueryHandler;
import com.buddycloud.channeldirectory.search.rsm.RSM;
import com.buddycloud.channeldirectory.search.utils.XMPPUtils;

/**
 * Channel Directory XMPP Component
 * Follows the XEP-0114 (http://xmpp.org/extensions/xep-0114.html)
 * 
 */
public class ChannelDirectoryComponent extends AbstractComponent {

    private static final String DESCRIPTION = "A pub sub search engine, "
            + "metadata crawler and recommendation service";
    private static final String NAME = "Channel Directory";
    private static final Logger LOGGER = Logger.getLogger(ChannelDirectoryComponent.class);

    private final Map<String, QueryHandler> queryHandlers = new HashMap<String, QueryHandler>();
    private final Properties properties;

    public ChannelDirectoryComponent(Properties properties) {
        this.properties = properties;
    }

    @Override
    public String getDescription() {
        return DESCRIPTION;
    }

    @Override
    public String getName() {
        return NAME;
    }

    @Override
    public void postComponentStart() {
        createHandlers();
    }

    /* (non-Javadoc)
     * @see org.xmpp.component.AbstractComponent#send(org.xmpp.packet.Packet)
     */
    @Override
    protected void send(Packet arg0) {
        LOGGER.debug("S: " + arg0.toXML());
        super.send(arg0);
    }

    @Override
    protected IQ handleIQGet(IQ iq) throws Exception {

        LOGGER.debug("R: " + iq.toXML());

        Element queryElement = iq.getElement().element("query");
        if (queryElement == null) {
            return XMPPUtils.error(iq, "IQ does not contain query element.", LOGGER);
        }

        Namespace namespace = queryElement.getNamespace();

        QueryHandler queryHandler = queryHandlers.get(namespace.getURI());
        if (queryHandler == null) {
            return XMPPUtils.error(iq, "QueryHandler not found for namespace: " + namespace, LOGGER);
        }

        return queryHandler.handle(iq);
    }

    @Override
    protected String[] discoInfoFeatureNamespaces() {
        ArrayList<String> namespaces = new ArrayList<String>(queryHandlers.keySet());
        namespaces.add(RSM.NAMESPACE);
        return (namespaces.toArray(new String[] {}));
    }

    @Override
    protected String discoInfoIdentityCategory() {
        return ("Search");
    }

    @Override
    protected String discoInfoIdentityCategoryType() {
        return ("Directory");
    }

    private void createHandlers() {

        ChannelDirectoryDataSource dataSource = null;
        try {
            dataSource = new ChannelDirectoryDataSource(properties);
        } catch (PropertyVetoException e) {
            throw new RuntimeException("Could not start data source", e);
        }

        addHandler(new NearbyQueryHandler(properties));
        addHandler(new MetadataQueryHandler(properties));
        addHandler(new ContentQueryHandler(properties));
        addHandler(new MostActiveQueryHandler(properties, dataSource));

        try {
            ChannelRecommender recommender = createRecommender(properties);
            addHandler(new RecommendationQueryHandler(properties, recommender));
            addHandler(new SimilarityQueryHandler(properties, recommender));
        } catch (Exception e) {
            LOGGER.warn("Could not create mahout-related handlers.", e);
        }
    }

    private ChannelRecommender createRecommender(Properties properties) {
        try {
            return new ChannelRecommender(properties);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    private void addHandler(QueryHandler queryHandler) {
        queryHandlers.put(queryHandler.getNamespace(), queryHandler);
    }
}