org.paxle.se.search.impl.SearchProviderCallable.java Source code

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Here is the source code for org.paxle.se.search.impl.SearchProviderCallable.java

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/**
 * This file is part of the Paxle project.
 * Visit http://www.paxle.net for more information.
 * Copyright 2007-2010 the original author or authors.
 *
 * Licensed under the terms of the Common Public License 1.0 ("CPL 1.0").
 * Any use, reproduction or distribution of this program constitutes the recipient's acceptance of this agreement.
 * The full license text is available under http://www.opensource.org/licenses/cpl1.0.txt
 * or in the file LICENSE.txt in the root directory of the Paxle distribution.
 *
 * Unless required by applicable law or agreed to in writing, this software is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 */

package org.paxle.se.search.impl;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Callable;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.osgi.framework.Constants;
import org.osgi.framework.ServiceReference;
import org.osgi.service.component.ComponentContext;
import org.paxle.core.doc.IIndexerDocument;
import org.paxle.se.query.tokens.AToken;
import org.paxle.se.search.ISearchProvider;
import org.paxle.se.search.ISearchRequest;
import org.paxle.se.search.ISearchResult;
import org.paxle.se.search.SearchProviderContext;

public class SearchProviderCallable implements Callable<ISearchResult> {

    /**
     * For logging
     */
    private final Log logger;

    /**
     * A list of search-results returned by the {@link #provider}
     */
    private final List<IIndexerDocument> results = new ArrayList<IIndexerDocument>();

    /**
     * The context of this component
     */
    protected ComponentContext ctx;

    /**
     * A reference to the {@link ISearchProvider} that should be used by this {@link Callable}
     */
    private final ServiceReference providerRef;

    /**
     * The search-request
     */
    private final ISearchRequest searchRequest;

    public SearchProviderCallable(ComponentContext ctx, ServiceReference providerRef,
            ISearchRequest searchRequest) {
        if (providerRef == null)
            throw new NullPointerException("Search provider-reference was null.");
        if (searchRequest == null)
            throw new NullPointerException("Search-request was null.");

        this.ctx = ctx;
        this.providerRef = providerRef;
        this.searchRequest = searchRequest;
        this.logger = LogFactory.getLog(getClass().getSimpleName());
    }

    public ISearchResult call() throws Exception {
        final long start = System.currentTimeMillis();

        String providerID = null;
        AToken query = null;
        try {
            // the search query to use
            query = this.searchRequest.getSearchQuery();

            // the provider to use
            final ISearchProvider provider = (ISearchProvider) this.ctx.getBundleContext()
                    .getService(this.providerRef);

            // the provider-ID (may be used to fetch additional metadata)
            providerID = (String) this.providerRef.getProperty(Constants.SERVICE_PID);

            this.logger.info(
                    "Starting search for '" + query + "' (" + this.searchRequest.getSearchQuery().toString() + ")");
            provider.search(this.searchRequest, this.results);
        } catch (InterruptedException e) {
            /* just fall through */
        } catch (Exception e) {
            this.logger
                    .error(String.format("Unexpected '%s' while performing a search for '%s' using provider '%s'.",
                            e.getClass().getName(), query, providerID), e);
        } finally {
            // context cleanup
            SearchProviderContext.removeCurrentContext();
        }
        return new SearchResult(providerID, this.results, System.currentTimeMillis() - start);
    }
}