com.aliasi.lingmed.server.SearchService.java Source code

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Here is the source code for com.aliasi.lingmed.server.SearchService.java

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/*
* LingPipe v. 2.0
* Copyright (C) 2003-5 Alias-i
*
* This program is licensed under the Alias-i Royalty Free License
* Version 1 WITHOUT ANY WARRANTY, without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the Alias-i
* Royalty Free License Version 1 for more details.
*
* You should have received a copy of the Alias-i Royalty Free License
* Version 1 along with this program; if not, visit
* http://www.alias-i.com/lingpipe/licenseV1.txt or contact
* Alias-i, Inc. at 181 North 11th Street, Suite 401, Brooklyn, NY 11211,
* +1 (718) 290-9170.
*/

package com.aliasi.lingmed.server;

import com.aliasi.lingmed.utils.FileUtils;

import com.aliasi.util.AbstractCommand;
import com.aliasi.util.Strings;

import java.io.File;
import java.io.IOException;

import java.rmi.RemoteException;

import java.util.Date;
import java.util.Properties;

import org.apache.lucene.index.IndexReader;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.store.FSDirectory;

import org.apache.log4j.Logger;

/**
 * <P>The <code>SearchService</code> command instantiates
 * a Lucene {@link org.apache.lucene.search.RemoteSearchable}
 * object for a local Lucene index and registers
 * this object with RMI, via a {@link SearchServer}.
 *
 * <P>The following arguments are all required:
 *
 * <dl>
 * <dt><code>-port</code></dt>
 * <dd>Port on which RMI registry service is listening.
 * </dd>
 *
 * <dt><code>-service</code></dt>
 * <dd>Name of service.  Used by RMI clients.
 * </dd>
 *
 * <dt><code>-index</code></dt>
 * <dd>Path to the Lucene index file.
 * </dd>
 * </dl>
 *
 * @author Mitzi Morris
 * @version 1.0
 * @since   LingMed1.0
 */

public class SearchService extends AbstractCommand {
    private final Logger mLogger = Logger.getLogger(SearchService.class);

    private String mIndexName;
    private String mService;
    private int mPort;

    private SearchServer mServer;
    private File mIndex;
    private long mVersion;

    private final static String LUCENE_INDEX = "index";
    private final static String PORT = "port";
    private final static String SERVICE = "service";

    private final static Properties DEFAULT_PARAMS = new Properties();
    static {
        DEFAULT_PARAMS.setProperty(PORT, "1099");
    }

    private final static int SECOND = 1000;
    private final static int MINUTE = 60 * SECOND;
    private final static int HOUR = 60 * 60 * SECOND;

    // Instantiate SearchService object and 
    // initialize instance variables per command line args
    private SearchService(String[] args) throws IOException, RemoteException {
        super(args, DEFAULT_PARAMS);
        mIndexName = getExistingArgument(LUCENE_INDEX);
        mService = getExistingArgument(SERVICE);
        mPort = getArgumentInt(PORT);
        reportParameters();

        mServer = new SearchServer(mPort);
        mLogger.info("search server instantiated on port: " + mPort);

        mIndex = FileUtils.checkIndex(mIndexName, false);
        mVersion = IndexReader.getCurrentVersion(mIndex);
        IndexSearcher searcher = new IndexSearcher(FSDirectory.getDirectory(mIndex));
        mLogger.info("instantiated index searcher, version: " + mVersion);
        mServer.registerSearcher(mService, searcher);
        mLogger.info("registered service: " + mService + " version: " + mVersion);
    }

    public void run() {
        try {
            while (true) {
                mLogger.info("check index versions");
                if (IndexReader.isLocked(mIndexName)) {
                    mLogger.info("index locked: " + mIndexName);
                } else if (mVersion != IndexReader.getCurrentVersion(mIndex)) {
                    mLogger.info("found new version of index for service: " + mService);
                    mVersion = IndexReader.getCurrentVersion(mIndex);
                    IndexSearcher searcher = new IndexSearcher(FSDirectory.getDirectory(mIndex));
                    mServer.registerSearcher(mService, searcher);
                    mLogger.info("re-registered service: " + mService + " version: " + mVersion);
                } else {
                    mLogger.info("index unchanged: " + mIndexName + " version: " + mVersion);
                }
                Thread.sleep(15 * MINUTE);
            }
        } catch (Exception e) {
            String msg = "Unexpected exception=" + e.getMessage();
            mLogger.warn(msg);
            try {
                mServer.unregisterSearcher(mService);
            } catch (RemoteException re) {
                mLogger.warn(re.getMessage());
            }
            IllegalStateException e2 = new IllegalStateException(msg);
            e2.setStackTrace(e.getStackTrace());
            throw e2;
        }
    }

    public static void main(String[] args) throws Exception {
        SearchService server = new SearchService(args);
        server.run();
    }

    private void reportParameters() {
        mLogger.info("Remote search server" + "\n\tStart time=" + Strings.msToString(startTimeMillis())
                + "\n\tIndex=" + mIndexName + "\n\tService=" + mService + "\n\tPort=" + mPort);
    }

}