Metacat

/**

 *    Purpose: A Class that searches a relational DB for elements and

 *             attributes that have free text matches a query string,

 *             or structured query matches to a path specified node in the

 *             XML hierarchy.  It returns a result set consisting of the

 *             document ID for each document that satisfies the query

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

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Matt Jones

 *     '$Date$'

 * '$Revision$'

 * 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

import java.io.*;

import java.net.MalformedURLException;

import java.sql.*;

import java.util.Stack;

import java.util.Hashtable;

import java.util.Enumeration;

/**

 * attributes that have free text matches a query string,

 * or structured query matches to a path specified node in the

 * XML hierarchy.  It returns a result set consisting of the

 * document ID for each document that satisfies the query

public class DBQuery {

  static final int WRITE = 2;

  static final int READ = 4;

  private String  parserName = null;

   * the main routine used to test the DBQuery utility.

   * Usage: java DBQuery <xmlfile>

  static public void main(String[] args) {

        System.err.println("Wrong number of arguments!!!");

     } else {

        try {

          // Open a connection to the database

          Connection dbconn = util.openDBConnection();

          String document = null;

  // following line removed by Dan Higgins to avoid insertion of query XML inside returned XML doc

  //        result.append("  <query>" + xmlfile + "</query>\n");

          while (doclist.hasMoreElements()) {

            result.append("  <document>\n    " + document +

                          "\n  </document>\n");

          }

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

          System.out.println(result);

        } catch (Exception e) {

          e.printStackTrace(System.err);

        }

     }

  }

  /**

   * construct an instance of the DBQuery class

   *

   * <p>Generally, one would call the findDocuments() routine after creating

   * an instance to specify the search query</p>

   *

   * @param conn the JDBC connection that we use for the query

                         SQLException,

  {

    return findDocuments(xmlquery, user, group, null);

  }

   * routine to search the elements and attributes looking to match query

   *

   * @param group the group of the user

   * @param returndoc an array of document types to backtrack against.

                                 String[] returndoc)

      String doctype = null;

//      String doctitle = null;

      String updateDate = null;

      String fieldname = null;

      String fielddata = null;

      if(returndoc != null)

      {//add the returndoc elements to a vector for easier manipulation

        for(int i=0; i<returndoc.length; i++)

        {

          returndocVec.add(new String((String)returndoc[i]));

        }

      }

        ResultSet rs = pstmt.getResultSet();

        boolean tableHasRows = rs.next();

        {

            tableHasRows = rs.next();

            continue;

          }

          doctype = rs.getString(3);

//          doctitle = rs.getString(4);

          createDate = rs.getString(4);

          updateDate = rs.getString(5);

          rev = rs.getInt(6);

          { //there are returndocs to match (backtracking can now be performed).

            btBuf.append("select object from xml_relation where ");

            btBuf.append("objdoctype in (");

            //build the doctype list for the backtracking sql statement

            for(int i=0; i<returndocVec.size(); i++)

            {

              btBuf.append("'").append((String)returndocVec.get(i)).append("'");

              if(i != (returndocVec.size() - 1))

              {

                btBuf.append(", ");

            btBuf.append(") ");

            btBuf.append("and subject like '");

            //btBuf.append("?docid=").append(docid).append("'");

            btBuf.append("%docid=").append(docid).append("'");

            npstmt.execute();

            ResultSet btrs = npstmt.getResultSet();

            if(hasBtRows)

            { //there was a backtrackable document found

              DocumentImpl xmldoc = null;

              {

              catch(Exception e)

              {

                                   "DBQuery.findDocuments: " + e.getMessage());

              docid   = xmldoc.getDocID();

              docname = xmldoc.getDocname();

              doctype = xmldoc.getDoctype();

//              doctitle = xmldoc.getDocTitle();

              updateDate = xmldoc.getUpdateDate();

              //System.out.println("docname: " + docname + " doctype: " + doctype +

              //                   " doctitle: " + doctitle + " createdate: " +

              //                   createDate + " updatedate: " + updateDate);

            }

          }

            completeDocid += rev;

            document.append("<docid>").append(completeDocid).append("</docid>");

              document.append("<docname>" + docname + "</docname>");

            }

            if (doctype != null) {

              document.append("<doctype>" + doctype + "</doctype>");

            }

//            if (doctitle != null) {

//              document.append("<doctitle>" + doctitle + "</doctitle>");

//            }

              document.append("<createdate>" + createDate + "</createdate>");

            }

            if(updateDate != null) {

              document.append("<updatedate>" + updateDate + "</updatedate>");

            }

            // Store the document id and the root node id

            docListResult.put(docid,(String)document.toString());

          // Advance to the next record in the cursor

          tableHasRows = rs.next();

        }

        if(qspec.containsExtendedSQL())

        {

          Vector extendedFields = new Vector(qspec.getReturnFieldList());

          Vector results = new Vector();

          StringBuffer doclist = new StringBuffer();

          while(keylist.hasMoreElements())

          {

            doclist.append("'");

            doclist.append((String)keylist.nextElement());

            doclist.append("',");

          }

          doclist.deleteCharAt(doclist.length()-1); //remove the last comma

          pstmt = dbconn.prepareStatement(qspec.printExtendedSQL(

          rs = pstmt.getResultSet();

          tableHasRows = rs.next();

          while(tableHasRows)

          {

            docid = rs.getString(1);

              // Advance to the next record in the cursor

              tableHasRows = rs.next();

              continue;

            }

            fielddata = rs.getString(3);

            document = new StringBuffer();

            tableHasRows = rs.next();

            if(docListResult.containsKey(docid))

            {

              String removedelement = (String)docListResult.remove(docid);

              docListResult.put(docid, removedelement + document.toString());

            }

            else

            {

              docListResult.put(docid, document.toString());

            }

          }

        //this code might be able to be added to the backtracking code above

        Enumeration docidkeys = docListResult.keys();

        while(docidkeys.hasMoreElements())

          String connstring = "%docid=";

          //                                           connstring + docidkey));

          pstmt = dbconn.prepareStatement(

          rs = pstmt.getResultSet();

          tableHasRows = rs.next();

          while(tableHasRows)

          {

            String sub = rs.getString(1);

            String rel = rs.getString(2);

            String obj = rs.getString(3);

            String objDT = rs.getString(5);

              String[] tempparam = murl.getParam(0);

              if(tempparam[0].equals("docid") && tempparam[1].equals(docidkey))

                document.append("<relation>");

                document.append("<relationtype>").append(rel);

                document.append("</relationtype>");

                document.append("<relationdoc>").append(obj);

                document.append("</relationdoc>");

                document.append("</relationdoctype>");

                String removedelement = (String)docListResult.remove(docidkey);

                docListResult.put(docidkey, removedelement + document.toString());

            }

          pstmt.close();

                           e.getMessage());

        try

        {

          dbconn.close();

        }

        catch(SQLException sqle)

        {

          System.out.println("error closing conn in DBQuery.findDocuments");

        }

      }

    //System.out.println(docListResult.toString());

  }

  /**

   * If the node appears more than once, the contents are returned

   * in the order in which they appearred in the document.

   * @param nodename the name or path of the particular node.

   * @param docid the docid of the document you want the node from.

   * @param conn a database connection-this allows this method to be static

   */

  public static Object[] getNodeContent(String nodename, String docid,

                                        Connection conn)

  {

    StringBuffer query = new StringBuffer();

    Vector result = new Vector();

    query.append("(select nodeid from xml_index where path like '");

    query.append(nodename);

    query.append("' and docid like '").append(docid).append("')");

    try

    {

      pstmt = conn.prepareStatement(query.toString());

      // Execute the SQL query using the JDBC connection

      pstmt.execute();

      ResultSet rs = pstmt.getResultSet();

      boolean tableHasRows = rs.next();

      while (tableHasRows)

      {

        result.add(rs.getString(1));

        System.out.println(rs.getString(1));

        tableHasRows = rs.next();

      }

    }

    catch (SQLException e)

    {

      try

      {

        pstmt.close();

      }

      catch(SQLException sqle) {}

    }

  }

  /**

   * to the pathquery.dtd and is appropriate for submission to the DBQuery

   * structured query engine

   *

   * @param params The list of parameters that  should be included in the query

   */

    StringBuffer query = new StringBuffer();

    Enumeration keys;

    String casesensitive = null;

    String searchmode = null;

    Object nextelement;

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

    {

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

    else

    {

      query.append("unspecified</meta_file_id>");

    }

//    query.append("<querytitle>");

//    if(params.containsKey("querytitle"))

//    {

//      query.append(((String[])params.get("querytitle"))[0]);

//      query.append("</querytitle>");

//    }

//    else

//    {

//      query.append("unspecified</querytitle>");

//    }

    if(params.containsKey("doctype"))

    {

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

    }

    else

    {

      doctype = "ANY";

    }

    {

      String[] returnfield = ((String[])params.get("returnfield"));

      for(int i=0; i<returnfield.length; i++)

      {

        query.append("<returnfield>").append(returnfield[i]);

        query.append("</returnfield>");

      }

    }

    {

      String[] owner = ((String[])params.get("owner"));

      for(int i=0; i<owner.length; i++)

      {

        query.append("<owner>").append(owner[i]);

        query.append("</owner>");

      }

    }

    if(params.containsKey("site"))

    {

      String[] site = ((String[])params.get("site"));

      for(int i=0; i<site.length; i++)

      {

        query.append("<site>").append(site[i]);

        query.append("</site>");

      }

    }

    //an empty returndoctype tag.

        !doctype.equals("ANY") &&

        !doctype.equals("") )

    {

       query.append("<returndoctype>");

       query.append(doctype).append("</returndoctype>");

    }

    {

      query.append("<returndoctype></returndoctype>");

    }

    //allows the dynamic switching of boolean operators

    if(params.containsKey("operator"))

    {

      query.append("<querygroup operator=\"" +

    else

    { //the default operator is UNION

      query.append("<querygroup operator=\"UNION\">");

    }

    {

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

    }

    else

    {

      casesensitive = "false";

    }

    if(params.containsKey("searchmode"))

    {

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

    }

    else

    {

      searchmode = "contains";

    }

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

    //query.  This is useful if the INTERSECT operator is used.

    if(params.containsKey("anyfield"))

       //allow for more than one value for anyfield

       for(int i=0; i<anyfield.length; i++)

         {

           query.append("<queryterm casesensitive=\"" + casesensitive +

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

                        "</value></queryterm>");

    //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();

      //parameters since the are already in the query

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

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

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

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

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

      {

        for(int i=0; i<((String[])nextelement).length; i++)

        {

          if(!((String[])nextelement)[i].equals(""))

          {

            query.append("<queryterm casesensitive=\"" + casesensitive +"\" " +

                         "<value>" +

                         "</value><pathexpr>" +

                         //add the path to query by

                         "</pathexpr></queryterm>");

          }

        }

    query.append("</querygroup></pathquery>");

  }

   * format a simple free-text value query as an XML document that conforms

   * to the pathquery.dtd and is appropriate for submission to the DBQuery

   * structured query engine

   *

   * @param value the text string to search for in the xml catalog

   * @param doctype the type of documents to include in the result set -- use

   *        "any" or "ANY" for unfiltered result sets

   */

   public static String createQuery(String value, String doctype) {

     StringBuffer xmlquery = new StringBuffer();

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

     xmlquery.append("<pathquery version=\"1.0\">");

     xmlquery.append("<meta_file_id>Unspecified</meta_file_id>");

//     xmlquery.append("<querytitle>Unspecified</querytitle>");

     if (!doctype.equals("any") && !doctype.equals("ANY")) {

       xmlquery.append("<returndoctype>");

       xmlquery.append(doctype).append("</returndoctype>");

     }

     xmlquery.append("<querygroup operator=\"UNION\">");

     //the if statement allows a query to gracefully handle a null

     //query.  Without this if a nullpointerException is thrown.

     if(!value.equals(""))

     {

       xmlquery.append("<queryterm casesensitive=\"false\" ");

       xmlquery.append("searchmode=\"contains\">");

       xmlquery.append("<value>").append(value).append("</value>");

       xmlquery.append("</queryterm>");

     }

     xmlquery.append("</pathquery>");