Metacat

/**

 *  '$RCSfile$'

 *    Purpose: A Class that tracks sessions for MetaCatServlet users.

 *  Copyright: 2000 Regents of the University of California and the

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Matt Jones

 *

 *   '$Author: jones $'

 *     '$Date: 2006-11-10 10:25:38 -0800 (Fri, 10 Nov 2006) $'

 * '$Revision: 3077 $'

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

package edu.ucsb.nceas.metacat;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.TimerTask;

import java.util.Vector;

import java.util.Iterator;

import edu.ucsb.nceas.metacat.MetaCatUtil;

import org.apache.log4j.Logger;

public class IndexingTimerTask extends TimerTask{

	 private Logger logMetacat = Logger.getLogger(IndexingTimerTask.class);

	 int count = 0;

	  /*

	     * Run a separate thread to build the XML index for this document.  This

	     * thread is run asynchronously in order to more quickly return control to

	     * the submitting user.  The run method checks to see if the document has

	     * been fully inserted before trying to update the xml_index table.

	     */

	    public void run()

	    {

	    	DBConnection dbConn = null;

	    	int serialNumber = 0;

	    	try{

	    		logMetacat.warn("Running indexing timer task");

	    		dbConn = DBConnectionPool.getDBConnection("IndexingThread");

	    		serialNumber = dbConn.getCheckOutSerialNumber();

	            Vector indexNamespaces = MetaCatUtil.getOptionList(MetaCatUtil.getOption("indexNamespaces"));

	            String nonJoinCriteria = "b.docid is NULL";

	    		boolean first = true;

	    		if(indexNamespaces != null && !indexNamespaces.isEmpty()){

	    			Iterator it = indexNamespaces.iterator();

	    			while(it.hasNext()){

	    				if(first){

	    					nonJoinCriteria = nonJoinCriteria + " AND (";

	    					nonJoinCriteria = nonJoinCriteria 

	    						+ " a.doctype like '" 

	    						+ it.next()

	    						+ "'";

	    					first = false;

	    				} else {

	    					nonJoinCriteria = nonJoinCriteria + " OR ";

	    					nonJoinCriteria = nonJoinCriteria 

	    						+ " a.doctype like '" 

	    						+ it.next()

	    						+ "'";

	    				}

	    			}

	    			nonJoinCriteria = nonJoinCriteria + ")";

	    		} else {

	    			// if no namespaces are defined in metacat.properties then return

	    			return;

	    		}

	    		String xmlDocumentsCheck = 

	    			MetaCatUtil.dbAdapter.getLeftJoinQuery("a.docid, a.rev", "xml_documents", 

	    					"xml_index", "a.docid = b.docid", nonJoinCriteria);

	    		PreparedStatement xmlDocCheck = dbConn.prepareStatement(xmlDocumentsCheck);

	    		// Increase usage count

	    		dbConn.increaseUsageCount(1);

	    		xmlDocCheck.execute();

	    		ResultSet rs = xmlDocCheck.getResultSet();

	    		boolean tableHasRows = rs.next();

	    		while (tableHasRows) {

	    			String docid = rs.getString(1);

	    			String rev = rs.getString(2);

	    			IndexingQueue.getInstance().add(docid, rev);

	    			tableHasRows = rs.next();

	            }

	    		rs.close();

	    		xmlDocCheck.close();

	       	} catch (SQLException se){

	       				se.printStackTrace();

		    } catch (Exception e){

	        		e.printStackTrace();

	        }finally {

	                DBConnectionPool.returnDBConnection(dbConn, serialNumber);

	        }

			logMetacat.warn("Indexing timer task returning");		

			count++;

	    }

}