Metacat

/**

 *  '$RCSfile$'

 *    Purpose: class that implements the MARINE interface to the 

 *             metadata database.

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

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Chad Berkley

 * 

 *   '$Author: berkley $'

 *     '$Date: 2000-08-07 08:13:15 -0700 (Mon, 07 Aug 2000) $'

 * '$Revision: 323 $'

 */

package edu.ucsb.nceas.metacat.marine;

import java.io.*;

import java.util.*;

import javax.servlet.*;

import javax.servlet.http.*;

import java.net.*;

import java.sql.*;

import org.xml.sax.*;

import org.xml.sax.helpers.*;

import edu.ucsb.nceas.metacat.*;

import oracle.jdbc.driver.*;

import oracle.xml.parser.v2.*;

import oracle.xml.parser.v2.XMLParser;

public class marineServlet extends edu.ucsb.nceas.metacat.MetaCatServlet 

{

	private marineUtil util;

	private String resultStyleURL;

	private String docStyleURL;

	private String xmlcatalogfile;

	private String saxparser;

	private String defaultdatapath;

	private String executescript;

	private DBQuery queryobj;

	private DBReader docreader;

	private DBTransform dbt;

	private Connection conn;

	private PropertyResourceBundle options;

	private String msg=null;

	private String queryname;

	private ServletConfig		config = null;

        private ServletContext	context = null;

	/**

	  Initializes the servlet and creates a connection to 

	  the database

 	**/

	public void init(PrintWriter out) 

	{

		util = new marineUtil();

		docStyleURL = util.getOption("docStyleURL");

		resultStyleURL = util.getOption("resultStyleURL");

		xmlcatalogfile = util.getOption("xmlcatalogfile");

      		saxparser = util.getOption("saxparser");

      		defaultdatapath = util.getOption("defaultdatapath");

      		executescript = util.getOption("executescript");

      		try

      		{

      		    conn = util.openDBConnection();  

      			queryobj = new DBQuery(conn,saxparser);

        		docreader = new DBReader(conn);

        		dbt = new DBTransform(conn);

      		}

      		catch(Exception e)

      		{

      			System.err.println("marineServlet: Error in init:");

      		    e.printStackTrace(System.err);

      		}

	}

	/**

	  Handles any GET requests 

	**/

	public void doGet (HttpServletRequest request, 

	                   HttpServletResponse response)

    			throws ServletException, IOException 

    	{

    		handleGetOrPost(request, response);

    	}

    	/**

    	  Handles and POST requests

    	**/

    	public void doPost (HttpServletRequest request, 

    	                    HttpServletResponse response)

    			throws ServletException, IOException 

    	{

    		handleGetOrPost(request, response);

    	}

    	/**

    	  This method is called from doGet and doPost.  It handles

    	  each request and sends back the response. It also handles

    	  the XSL tranformations

    	**/

    	private void handleGetOrPost(HttpServletRequest request, 

    			HttpServletResponse response) 

    			throws ServletException, IOException 

    	{

    		response.setContentType("text/html");

    		PrintWriter out = response.getWriter();

    		try

    		{

    			init(out);

		}

    		catch(Exception e)

      		{

      			System.err.println("marineServlet: Exception in init in handleGetOrPost (try1): ");

      			e.printStackTrace(System.err);

      		}

    		String name = null;

    		String[] value = null;

    		String[] docid = new String[3];

    		Hashtable params = new Hashtable();

    		Enumeration paramlist = request.getParameterNames();

    		while (paramlist.hasMoreElements()) 

    		{

      			name = (String)paramlist.nextElement();

      			value = request.getParameterValues(name);

      			// Decode the docid and mouse click information

      			if (name.endsWith(".y")) 

      			{

        			docid[0] = name.substring(0,name.length()-2);

        			//out.println("docid => " + docid[0]);

        			params.put("docid", docid);

        			name = "ypos";

      			}

      			if (name.endsWith(".x")) 

      			{

        			name = "xpos";

      			}

      			//out.println(name + " => " + value[0]);

      			params.put(name,value);

    		}

		// Determine what type of request the user made

    		// if the action parameter is set, use it as a default

    		// but if the ypos param is set, calculate the action

    		// needed

    		String action = ((String[])params.get("action"))[0];

    		long ypos = 0;

    		try 

    		{

      			ypos = (new Long(

      			((String[])params.get("ypos"))[0]).longValue());

      			//out.println("<P>YPOS IS " + ypos);

      			if (ypos <= 20) 

      			{

        			action = "viewabstract";

      			} 

      			else if (ypos > 20 && ypos <= 45) 

      			{

        			action = "viewdocumentation";

      			} 

      			else if (ypos > 45) 

      			{

        			action = "download";

      			}

    		} 

    		catch (Exception npe) 

    		{

    			System.err.println("marineServlet: Error in handleGetOrPost (try2): ");

      			npe.printStackTrace(System.err);

    		}

    		//Jivka's login code should go here!

    		try{

    		   if(action.equals("query") || action.equals("squery")) 

    		   {

    		      //send any type of query action to handleQueryAction

      			   handleQueryAction(out, params, response);

    		   }

    		   else if(action.equals("init"))

    		   {

    		   	   handleInitAction(out);

    		   }

    		   else if(action.equals("viewabstract"))

    		   {

    		       //when the user clicks the view abstract graphic

    			   handleViewAbstractAction(out, params, response);

    		   }

    		   else if(action.equals("viewdocumentation"))

    		   {

    		       //when the user clicks the view documentation graphic

    		 	   handleViewDocumentationAction(out, params, response);

    		   }

    		   else if(action.equals("download"))

    		   {

    		       //when the user clicks the download graphic

    			   handleDownloadAction(out, params, response);

    		   }

    		   else 

    		   {

      			   out.println("Error: action " + action + " not registered" +

      			               "Please report this error.");

    		   }

    		   conn.close();

    		}

		catch(Exception e)

		{

			System.err.println("marineServlet: Error in handleGetOrPost (try3)");

			e.printStackTrace(System.err);

		}

		System.err.println("msg: " + msg);

		out.close();

    	}

        /**

          Handles when the user clicks the View Abstract graphic.

        **/

	private void handleViewAbstractAction(PrintWriter out, Hashtable params, 

               HttpServletResponse response)

        {

         	PreparedStatement pstatement;

         	ResultSet rs = null;

        	String markup = null;

        	String docid = ((String[])params.get("docid"))[0];

        	//this query is based on the eml-resource datatype

        	//it will NOT work with eml-dataset documents because

        	//eml-dataset removes the abstract data an extra level

        	//from the <abstract> tag.

        	String querysql = "select nodedata from xml_nodes" +

                             " where parentnodeid in" +

                             " (select nodeid from xml_nodes where" +

                             " nodename like 'abstract') and docid like '" +

                             docid + "'";

                try{

                   //create the query, execute it, get the result

                   pstatement = conn.prepareStatement(querysql);

                   pstatement.execute();

                   rs = pstatement.getResultSet();

                   boolean moreRows = rs.next();

                   //print out the html.  This does not use any XSL

                   markup = "<html><body bgcolor=\"white\"><h1>Abstract</h1>";

                   while(moreRows)

                   {

                	   markup += "<p>" + rs.getString(1) + "</p>";

                	   moreRows = rs.next();

                   }

                   markup += "</body></html>";

                   }

                catch(SQLException sqle)

                {

                	System.err.println("marineServlet: SQLError " +

                	                   "in handleViewAbstractAction");

                	sqle.printStackTrace(System.err);

                } 

                catch(Exception e)

                {

                	System.err.println("marineServlet: Error " +

                	                   "in handleViewAbstractAction");

                	e.printStackTrace(System.err);

                }

                out.println(markup); //send the output to the browser

        }

        /**

          Handles when the user clicks the View Documentation graphic.

        **/

        private void handleViewDocumentationAction(PrintWriter out, Hashtable params, 

               HttpServletResponse response)

        {

        	String doc = null;

        	String docid = ((String[])params.get("docid"))[0];

        	out.println("view documentation not yet implemented");

		try{        	

        	    doc = docreader.readXMLDocument(docid);

        	    XMLDocumentFragment htmldoc = null;

        	    XSLStylesheet style = new XSLStylesheet(

                                    new URL(docStyleURL), null);

          	    htmldoc = (new XSLProcessor()).processXSL(style, 

                                   (Reader)(new StringReader

                                   (doc)),null);

          	    htmldoc.print(out);

          	}

          	catch(Exception e)

          	{

          		System.err.println("marineServlet: error in " +

          		                   "handleViewDocumentationAction");

          		e.printStackTrace(System.err);

          	}

        }

        private void handleInitAction(PrintWriter out)

        {

        	try{

      			StringBuffer temp = new StringBuffer();

      			XMLDocumentFragment html = null;

      			temp.append("<?xml version=\"1.0\"?>\n");

      		    temp.append("<resultset></resultset>\n");

      		    //create a null query and run it through the

      		    //xsl processor to create the opening page      			

      			XSLStylesheet style = new XSLStylesheet(

                                 new URL(resultStyleURL), null);

           	    html = (new XSLProcessor()).processXSL(style, 

                                   (Reader)(new StringReader(temp.toString())), null);

          		html.print(out);

                }

                catch(Exception e)

          	{

          		System.err.println("marineServlet: error in handleQueryAction (try1)");

          		e.printStackTrace(System.err);

          	}

        }

        /**

          Handles when the user clicks the Download graphic.

        **/

        private void handleDownloadAction(PrintWriter out, Hashtable params, 

               HttpServletResponse response)

	{

		out.println("download not yet implemented");

	}

	/**

	  This method handles any and all query requests including the 

	  init request.  It separates the queries into 3 classes.

	  1) query-This executes a free text search.

	  2) squery-This executes a structured query.

	  3) init-This executes a null query.

	  After executing the query, the xml results are sent through

	  the XSL processor and returned to the browser as HTML (if

	  qformat="html").  If qformat="xml" the xml document is returned

	  without transformation.

	**/

  	private void handleQueryAction(PrintWriter out, Hashtable params, 

               HttpServletResponse response)

        {

        	String query = ((String[])params.get("query"))[0];

      		String action = ((String[])params.get("action"))[0];

      		Hashtable doclist = null;

      		String[] doctypeArr = null;

      		String doctype = null;

      		Reader xmlquery = null;

      		Hashtable extendedQuery = new Hashtable();

      		if(action.equals("query")) 

      		{

       	 		doctypeArr = (String[])params.get("doctype");

        		doctype = null;

        		if (doctypeArr != null) 

        		{

          			doctype = ((String[])params.get("doctype"))[0]; 

        		}

        		if (doctype != null) 

        		{

          			xmlquery = new StringReader(DBQuery.createQuery(query,doctype));

        		} 

        		else 

        		{

          			xmlquery = new StringReader(DBQuery.createQuery(query));

        		}

      		} 

      		else if(action.equals("squery")) 

      		{ 

      			doctypeArr = (String[])params.get("doctype");

        		doctype = null;

        		if (doctypeArr != null) 

        		{

          			doctype = ((String[])params.get("doctype"))[0]; 

        		}

        		// for some reason the doctype="ANY" wildcard is not working

        		//correctly. For this reason, I have ommited the doctype

        		//here for the time being (7/20). 

        		xmlquery = new StringReader(createSQuery(params));

      		} 

      		else if(action.equals("init"))

      		{

      			try{

      			   StringBuffer temp = new StringBuffer();

      			   XMLDocumentFragment html = null;

      			   temp.append("<?xml version=\"1.0\"?>\n");

      		       temp.append("<resultset></resultset>\n");

      		       //create a null query and run it through the

      		       //xsl processor to create the opening page      			

      			   XSLStylesheet style = new XSLStylesheet(

                                    new URL(resultStyleURL), null);

          		   html = (new XSLProcessor()).processXSL(style, 

                                   (Reader)(new StringReader(temp.toString())), null);

          		   html.print(out);

          		   }

          		catch(Exception e)

          		{

          			System.err.println("marineServlet: error in handleQueryAction (try1)");

          			e.printStackTrace(System.err);

          		}

      		}

      		else 

      		{

        		msg += "marineServlet: Error handling query -- illegal action value";

      		}

      		if (queryobj != null) 

      		{

      			doclist = queryobj.findDocuments(xmlquery);

      			//msg += "\n\n" + doclist.toString();

      		} 

      		else 

      		{

        		out.println("marineServlet: Query Object Init failed.");

        		return;

      		}

 		//get the date_created, date_updated, organization

 		//and owner information for the query request

 		extendedQuery = createExtendedQuery(doclist);

      		// Create a buffer to hold the xml result

      		StringBuffer resultset = new StringBuffer();

      		// Print the resulting root nodes

      		String docid;

      		String document = null;

      		resultset.append("<?xml version=\"1.0\"?>\n");

      		resultset.append("<resultset>\n");

      		//queryname contains the xmlquery.  This sends the query

      		//itself back to the page to refresh the text boxes

      		//Without the queryname, the text boxes do not retain their

      		//values between queries.

      		resultset.append("  <query>" + queryname + "</query>");

      		Enumeration doclistkeys = doclist.keys(); 

      		//add the returned documents to the xml result

      		while(doclistkeys.hasMoreElements()) 

      		{

        		docid = (String)doclistkeys.nextElement();

        		document = (String)doclist.get(docid);

        		if(extendedQuery.containsKey(docid))

        		{

        			resultset.append("  <document>" + document +

        			          extendedQuery.get(docid).toString() +

        			          "</document>");

        		}

        		else

        		{

        			resultset.append("  <document>" + document + 

        		                 "</document>");

        		}

      		}

      		resultset.append("</resultset>");

      		String qformat = ((String[])params.get("qformat"))[0]; 

      		if (qformat.equals("xml")) 

      		{

        		// set content type and other response 

        		// header fields first

        		response.setContentType("text/xml");

        		out.println(resultset.toString());

      		} 

      		else if(qformat.equals("html")) 

      		{

        		// set content type and other response header

        		// fields first

        		response.setContentType("text/html");

			//transform the xml to html with XSL

        		XMLDocumentFragment htmldoc = null;

        		try  

        		{

          			XSLStylesheet style = new XSLStylesheet(

                                    new URL(resultStyleURL), null);

          			htmldoc = (new XSLProcessor()).processXSL(style, 

                                   (Reader)(new StringReader

                                   (resultset.toString())),null);

          			htmldoc.print(out);

        		} 

        		catch (Exception e) 

        		{

          			System.err.println("marineServlet: error in handleQueryAction (try2)"); 

          	        e.printStackTrace(System.err);

        		}

      		}

      	}

      	/**

      	   creates the sql query for the extended information

      	   displayed upon successful query

      	**/

      	private Hashtable createExtendedQuery(Hashtable docs)

      	{

      		Hashtable result = new Hashtable();

      		ResultSet givenNameResults = null;

      		ResultSet surNameResults = null;

      		ResultSet organizationNameResults = null;

      		ResultSet dateResults = null;

      		String docid = null;

      		String data = null;

      		Object docidObj = null;

      		PreparedStatement pstatement;

      		Enumeration docids = docs.keys();

      		//find all of the owners first names

		String givenNameQuery = "select docid, nodedata from xml_nodes" +

		   " where parentnodeid in" +

		   " (select nodeid from xml_index where path like 'givenName')" +

		   " and parentnodeid in" +

 		   " (select nodeid from xml_nodes where nodename like 'givenName'" +

  		   " and parentnodeid in" +

                   " (select nodeid from xml_nodes where nodename like 'individualName'" +

                   " and parentnodeid in" +

                   " (select parentnodeid from xml_nodes where nodename like 'roleCode'" +

                   " and nodeid in" +

                   " (select parentnodeid from xml_nodes where" +

                   " nodedata = 'Owner'" +

                   " and parentnodeid in" +

                   " (select nodeid from xml_index where path like 'roleCode')))))";

                //find all of the owners last names

		String surNameQuery = "select docid, nodedata from xml_nodes" +

		   " where parentnodeid in" +

		   " (select nodeid from xml_index where path like 'surName')" +

		   " and parentnodeid in" +

 		   " (select nodeid from xml_nodes where nodename like 'surName'" +

  		   " and parentnodeid in" +

                   " (select nodeid from xml_nodes where nodename like 'individualName'" +

                   " and parentnodeid in" +

                   " (select parentnodeid from xml_nodes where nodename like 'roleCode'" +

                   " and nodeid in" +

                   " (select parentnodeid from xml_nodes where" +

                   " nodedata = 'Owner'" +

                   " and parentnodeid in" +

                   " (select nodeid from xml_index where path like 'roleCode')))))";

		//find all of the organizations

		String organizationNameQuery = "select docid, nodedata from xml_nodes" +

		   " where parentnodeid in" +

		   " (select nodeid from xml_index where path like 'organizationName')";

                //find all of the creation and update dates

                String dateQuery = "select docid, date_created, date_updated" +

                   " from xml_documents";

            //execute the queries

            try{  

                pstatement = conn.prepareStatement(givenNameQuery);

                pstatement.execute();

                givenNameResults = pstatement.getResultSet();

                pstatement = conn.prepareStatement(surNameQuery);

                pstatement.execute();

                surNameResults = pstatement.getResultSet();

		pstatement = conn.prepareStatement(organizationNameQuery);

                pstatement.execute();

                organizationNameResults = pstatement.getResultSet();

      		pstatement = conn.prepareStatement(dateQuery);

                pstatement.execute();

                dateResults = pstatement.getResultSet();

                }

             catch(Exception e)

             {

                System.err.println("marineServlet: error in createExtendedQuery(try1)");

                e.printStackTrace(System.err);

             }

             try{

                 boolean moreRows = givenNameResults.next();

                 //add the givenName information to the xml.

                 while(moreRows)

                 {

                 	docid = givenNameResults.getString(1);

             	    data = givenNameResults.getString(2);

             	    //check if the original result set contains this docid

             	    if(docs.containsKey(docid))

             	    {

             		    String markup = "<givenName>" + data + "</givenName>";

             		    result.put(docid, markup);

             	    }

             	    moreRows = givenNameResults.next();

                 }	

                 moreRows = surNameResults.next();

                 //add the surName information to the xml.

                 while(moreRows)

                 {

             	    docid = surNameResults.getString(1);

             	    data = surNameResults.getString(2);

             	    //check if the original result set contains this docid

             	    if(docs.containsKey(docid))

             	    {

             		    //check if this key is already in the result hashtable

             		    //i.e. there was a givenName for that docid.

             		    if(result.containsKey(docid))

             		    {

             			    String markup = result.get(docid).toString();

             			    markup += "<surName>" + data + "</surName>";

             			    result.remove(docid);

             			    result.put(docid, markup);

             		    }

             		    else

             	 	    { 

             			    String markup = "<surName>" + data + "</surName>";

             			    result.put(docid, markup);

             		    }

             	    }

             	    moreRows = surNameResults.next();

                 }

                 //add the organizationName information to the xml.

                 moreRows = organizationNameResults.next();

                 while(moreRows)

                 {

             	    docid = organizationNameResults.getString(1);

             	    data = organizationNameResults.getString(2);

             	    //check if the original result set contains this docid

             	    if(docs.containsKey(docid))

             	    {

             		    //check if this key is already in the result hashtable

             		    //i.e. there was a givenName for that docid.

             		    if(result.containsKey(docid))

             		    {

             			    String markup = result.get(docid).toString();

             			    markup += "<organizationName>" + data + "</organizationName>";

             			    result.remove(docid);

             			    result.put(docid, markup);

             		    }

             		    else

             	 	    { 

             			    String markup = "<organizationName>" + data + "</organizationName>";

             			    result.put(docid, markup);

             		    }

             	    }

             	    moreRows = organizationNameResults.next();

                 }

                 moreRows = dateResults.next();

                 //add the date information to the xml.

                 while(moreRows)

                 {

             	    docid = dateResults.getString(1);

             	    data = dateResults.getString(2); //date_created

             	    String data2 = dateResults.getString(3); //date_updated

             	    //check if the original result set contains this docid

             	    if(docs.containsKey(docid))

             	    {

             		    //check if this key is already in the result hashtable

             		    //i.e. there was a givenName for that docid.

             		    if(result.containsKey(docid))

             		    {

             			    String markup = result.get(docid).toString();

             			    markup += "<date_created>" + data + "</date_created>";

             			    markup += "<date_updated>" + data2 + "</date_updated>";

             			    result.remove(docid);

             			    result.put(docid, markup);

             		    }

             		    else

             	 	    { 

             			    String markup = "<date_created>" + data + "</date_created>";

             			    markup += "<date_updated>" + data2 + "</date_updated>";

             			    result.put(docid, markup);

             		    }

             	    }

             	    moreRows = dateResults.next();

                 }

             }

             catch(Exception e)

             {

             	System.err.println("marineServlet: error in createExtendedQuery(try2)");

                e.printStackTrace(System.err);

             }

             return result;

      	}

      	/**

      	   creates the xml query for the browse list

      	**/

      	private String createBrowseList()

      	{

      		String query;

      		query = "<?xml version=\"1.0\"?>";

		query += "<!DOCTYPE pathquery PUBLIC \"-//NCEAS//pathquery-1.0//EN\" " + 

          		    "\"http://alpha.nceas.ucsb.edu/xmltodb/lib/pathquery.dtd\" >";

    		query += "<pathquery version=\"1.0\">";

    		query += "<meta_file_id>unspecified</meta_file_id>";

    		query += "<querytitle>unspecified</querytitle>";

    		query += "<querygroup operator=\"union\">";

    		query += "<queryterm casesensitive=\"false\" " + 

    				         "searchmode=\"contains\">";

    		query += "<value>";

    		query += "%";           //return everything

    		query += "</value>";

    		query += "</queryterm>";

    		query += "</querygroup></pathquery>";

    		return query;

      	}

      	/** takes in the parameter list from the input source and 

      	    a doctype and returns a structured xml query based

      	    on the parameters.

      	**/

      	private String createSQuery(Hashtable params, String doctype)

	{

    		String query;

    		Enumeration elements;

    		Enumeration keys;

    		Object nextkey;

    		Object nextelement;

    		queryname = " ";

    		query = "<?xml version=\"1.0\"?>";

		query += "<!DOCTYPE pathquery PUBLIC \"-//NCEAS//pathquery-1.0//EN\" " + 

          		    "\"http://alpha.nceas.ucsb.edu/xmltodb/lib/pathquery.dtd\" >";

    		query += "<pathquery version=\"1.0\"><meta_file_id>";

    		if(params.containsKey("meta_file_id"))

    		{

    			query += ((String[])params.get("meta_file_id"))[0];

    			query += "</meta_file_id>";

    		}

    		else

    		{

    			query += "unspecified</meta_file_id>";

    		}

    		query += "<querytitle>";

    		if(params.containsKey("querytitle"))

    		{

    			query += ((String[])params.get("querytitle"))[0];

    			query += "</querytitle>";

    		}

    		else

    		{

    			query += "unspecified</querytitle>";

    		}

    		if(!doctype.equals(""))

    		{

    			query += "<returndoctype>" + doctype + "</returndoctype>";

    		}

    		query += "<querygroup operator=\"" + 

    		         ((String[])params.get("operator"))[0] + "\">";

    		//anyfield is a special case because it does a 

    		//free text search.  It does not have a <pathexpr>

    		//tag.

    		if(params.containsKey("anyfield") && 

    		   !((String[])params.get("anyfield"))[0].equals(""))

    		{

    			query += "<queryterm casesensitive=\"false\" " +

    			         "searchmode=\"contains\"><value>" +

    			         ((String[])params.get("anyfield"))[0] +

    			         "</value></queryterm>";

    			         queryname += "<anyfield>";

    			         queryname += ((String[])params.get("anyfield"))[0];

    			         queryname += "</anyfield>";

    		}

    		//this while loop finds the rest of the parameters

    		//and attempts to query for the field specified

    		//by the parameter.

    		elements = params.elements();

    		keys = params.keys();

    		while(keys.hasMoreElements() && elements.hasMoreElements())

    		{

    			nextkey = keys.nextElement();

    			nextelement = elements.nextElement();

    			//make sure we aren't querying for any of these

    			//parameters.

    			if(!nextkey.toString().equals("doctype") && 

    			   !nextkey.toString().equals("action")  &&

    			   !nextkey.toString().equals("qformat") && 

    			   !nextkey.toString().equals("anyfield") &&

    			   !nextkey.toString().equals("operator") &&

    			   !(((String[])nextelement)[0].equals("")) )

    			{

    				query += "<queryterm casesensitive=\"false\" " + 

    				         "searchmode=\"contains\">";

    				query += "<value>";

    				//add the query value

    				query += ((String[])nextelement)[0];

    				query += "</value><pathexpr>" +

    				//add the path to query by 

    				         nextkey.toString() + 

    				         "</pathexpr></queryterm>";

    				//add the query back into the xml to fill in 

    				//the text boxes.

    				queryname += "<" + nextkey.toString() + ">";

    				queryname += ((String[])nextelement)[0];

    				queryname += "</" + nextkey.toString() + ">";

    			}

    		}

    		query += "</querygroup></pathquery>";

    		return query;

        } 

        /**same as createSQuery(Hashtable, String) except

           no doctype is required.

        **/

        private String createSQuery(Hashtable params)

        {

        	return createSQuery(params, "");

        } 

}