Metacat

/**

 *  '$RCSfile$'

 *    Purpose: A Class that writes an XML document main data

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

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Jivka Bojilova, Matt Jones

 *

 *   '$Author: bojilova $'

 *     '$Date: 2000-08-03 16:15:11 -0700 (Thu, 03 Aug 2000) $'

 * '$Revision: 312 $'

 */

package edu.ucsb.nceas.metacat;

import java.sql.*;

import java.io.IOException;

import java.util.Hashtable;

import java.util.Enumeration;

/** 

 * A Class that writes an XML document main data to a database connection

 */

public class DBSAXDocument {

    private Connection      conn;

    private long            rootnodeid;

    private String          docname;

    private String          doctype;

    private String          doctitle;

    private String          docid;

    /** 

     * Construct a new document instance

     *

     * @param conn the JDBC Connection to which all information is written

     * @param rootnodeid - sequence id of the root node in the document

     * @param docname - the name of DTD, i.e. the name immediately following 

     *        the DOCTYPE keyword ( should be the root element name ) or

     *        the root element name if no DOCTYPE declaration provided

     *        (Oracle's and IBM parsers are not aware if it is not the 

     *        root element name)

     * @param doctype - Public ID of the DTD, i.e. the name immediately 

     *                  following the PUBLIC keyword in DOCTYPE declaration or

     *                  the docname if no Public ID provided or

     *                  null if no DOCTYPE declaration provided

     *

     */

    public DBSAXDocument (Connection conn, long rootnodeid, String docname, 

                          String doctype, String docid, String action)

                          throws AccessionNumberException {

      this.conn = conn;

      this.rootnodeid = rootnodeid;

      this.docname = docname;

      this.doctype = doctype;

      this.docid = docid;

      writeDocumentToDB(action);

    }

    /** 

     * Construct a new document instance, used for deleting documents

     *

     * @param conn the JDBC Connection to which all information is written

     */

    public DBSAXDocument (Connection conn) {

      this.conn = conn;

    }

    /** creates SQL code and inserts new document into DB connection */

    private void writeDocumentToDB(String action) 

                          throws AccessionNumberException {

        try {

          PreparedStatement pstmt = null;

          if (action.equals("INSERT")) {

            this.docid = AccessionNumber.generate(docid, "INSERT");

            pstmt = conn.prepareStatement(

                "INSERT INTO xml_documents " +

                "(docid, rootnodeid, docname, doctype, " +

                "date_created, date_updated) " +

                "VALUES (?, ?, ?, ?, sysdate, sysdate)");

            // Bind the values to the query

            pstmt.setString(1, this.docid);

            pstmt.setLong(2, rootnodeid);

            pstmt.setString(3, docname);

            pstmt.setString(4, doctype);

          } else if (action.equals("UPDATE")) {

            // Determine if the docid is OK for an UPDATE

            this.docid = AccessionNumber.generate(docid, "UPDATE");

            // Save the old document entry in a backup table

            saveDocument(docid);

            // Update the new document to reflect the new node tree

            pstmt = conn.prepareStatement(

                "UPDATE xml_documents " +

                "SET rootnodeid = ?, docname = ?, doctype = ?, " +

                "date_updated = sysdate WHERE docid LIKE ?");

            // Bind the values to the query

            pstmt.setLong(1, rootnodeid);

            pstmt.setString(2, docname);

            pstmt.setString(3, doctype);

            pstmt.setString(4, this.docid);

          } else {

            System.err.println("Action not supported: " + action);

          }

          // Do the insertion

          pstmt.execute();

          pstmt.close();

        } catch (SQLException e) {

          System.out.println(e.getMessage());

        } catch (AccessionNumberException ane) {

          MetaCatUtil.debugMessage("Invalid accession number.");

          MetaCatUtil.debugMessage(ane.getMessage());

          throw ane;

        } catch (Exception e) {

          System.out.println(e.getMessage());

        }

    }

    /** Get doctype */

    public String getDoctype() {

      return doctype;

    }

    /** Get doc id */

    public String getDocID() {

      return docid;

    }

    /** Get root node id */

    public long getRootNodeID() {

      return rootnodeid;

    }

    /**

     * Get the document title

     */

    public String getTitle() {

      return doctitle;

    }

    /**

     * Set the document title

     *

     * @param title the new title for the document

     */

    public void setTitle( String title ) {

      this.doctitle = title;

      try {

        PreparedStatement pstmt;

        pstmt = conn.prepareStatement(

              "UPDATE xml_documents " +

              " SET doctitle = ? " +

              "WHERE docid = ?");

        // Bind the values to the query

        pstmt.setString(1, doctitle);

        pstmt.setString(2, docid);

        // Do the insertion

        pstmt.execute();

        pstmt.close();

      } catch (SQLException e) {

        System.out.println(e.getMessage());

      }

    }

    /**

     * Look up the title of the first child element named "title"

     * and record it as the document title

     */

    public void setTitleFromChildElement() {

        String title = null;

        long assigned_id=0;

        PreparedStatement pstmt;

        try {

          pstmt = conn.prepareStatement(

                  "SELECT nodedata FROM xml_nodes " +

                  "WHERE nodetype = 'TEXT' " +

                  "AND rootnodeid = ? " +

                  "AND parentnodeid IN " +

                  "  (SELECT nodeid FROM xml_nodes " +

                  "  WHERE nodename = 'title' " +

                  "  AND nodetype =  'ELEMENT' " +

                  "  AND rootnodeid = ? ) " +

                  "ORDER BY nodeid");

          // The above query might be slow, and probably will be because

          // it gets ALL of the title elements while searching for one

          // title in a small subtree but it avoids the problem of using

          // Oracle's Hierarchical Query syntax which is not portable --

          // the commented out SQL that follows shows an equivalent query

          // using Oracle-specific hierarchical query

/*

          pstmt = conn.prepareStatement(

                  "SELECT nodedata FROM xml_nodes " +

                  "WHERE nodetype = 'TEXT' " +

                  "AND parentnodeid IN " +

                  "(SELECT nodeid FROM xml_nodes " +

                  "WHERE nodename = 'title' " +

                  "START WITH nodeid = ? " +

                  "CONNECT BY PRIOR nodeid = parentnodeid)");

*/

          // Bind the values to the query

          pstmt.setLong(1, rootnodeid);

          pstmt.setLong(2, rootnodeid);

          pstmt.execute();

          ResultSet rs = pstmt.getResultSet();

          boolean tableHasRows = rs.next();

          if (tableHasRows) {

            title = rs.getString(1);

          }

          pstmt.close();

        } catch (SQLException e) {

          System.out.println("Error getting id: " + e.getMessage());

        }

        // assign the new title

        this.setTitle(title);

    }

  /** Save a document entry in the xml_revisions table */

  public void saveDocument(String docid) throws SQLException {

    // First get all of the values we need

    long rnodeid = -1;

    String docname = null;

    String doctype = null;

    String doctitle = null;

    Date date_created = null;

    PreparedStatement pstmt = conn.prepareStatement(

       "SELECT rootnodeid, docname, doctype, doctitle, date_created " +

       "FROM xml_documents " +

       "WHERE docid = ?");

    // Bind the values to the query and execute it

    pstmt.setString(1, docid);

    pstmt.execute();

    ResultSet rs = pstmt.getResultSet();

    boolean tableHasRows = rs.next();

    if (tableHasRows) {

      rnodeid      = rs.getLong(1);

      docname      = rs.getString(2);

      doctype      = rs.getString(3);

      doctitle     = rs.getString(4);

      date_created = rs.getDate(5);

    }

    pstmt.close();

    MetaCatUtil.debugMessage(new Long(rnodeid).toString());

    MetaCatUtil.debugMessage(docname);

    MetaCatUtil.debugMessage(doctitle);

    //MetaCatUtil.debugMessage(date_created.toString());

    // Next create the new record in the other table using the values selected

    pstmt = conn.prepareStatement(

       "INSERT INTO xml_revisions " +

       "(revisionid, docid, rootnodeid, docname, doctype, doctitle, " +

       "date_created, date_updated) " +

       "VALUES (null, ?, ?, ?, ?, ?, sysdate, sysdate)");

    // Bind the values to the query and execute it

    pstmt.setString(1, docid);

    pstmt.setLong(2, rnodeid);

    pstmt.setString(3, docname);

    pstmt.setString(4, doctype);

    pstmt.setString(5, doctitle);

    //pstmt.setDate(6, date_created);

    pstmt.execute();

    pstmt.close();

  }

}

/**

 * '$Log$

 * 'Revision 1.15  2000/06/27 04:31:07  jones

 * 'Fixed bugs associated with the new UPDATE and DELETE functions of

 * 'DBWriter.  There were problematic interactions between some static

 * 'variables used in DBEntityResolver and the way in which the

 * 'Servlet objects are re-used across multiple client invocations.

 * '

 * 'Generally cleaned up error reporting.  Now all errors and success

 * 'results are reported as XML documents from MetaCatServlet.  Need

 * 'to make the command line tools do the same.

 * '

 * 'Revision 1.14  2000/06/26 10:35:05  jones

 * 'Merged in substantial changes to DBWriter and associated classes and to

 * 'the MetaCatServlet in order to accomodate the new UPDATE and DELETE

 * 'functions.  The command line tools and the parameters for the

 * 'servlet have changed substantially.

 * '

 * 'Revision 1.13.2.8  2000/06/26 08:38:02  jones

 * 'Added DELETE feature to DBWriter.  Now takes an action "DELETE" and a

 * 'docid and will move the record from the xml_documents table to the

 * 'xml_revisions table.

 * 'Modified option parsing to support option symbols on command line.

 * '

 * 'Revision 1.13.2.7  2000/06/26 03:04:31  jones

 * 'Completed UPDATE function.  Included new table "xml_revisions" to store a

 * 'single document record for each revision to a document.  It is identical

 * 'to "xml_documents" with the addition of a "revisionid" column to

 * 'allow more than one revision per docid.

 * '

 * 'Revision 1.13.2.6  2000/06/26 02:02:20  jones

 * 'Continued fixing problems with exception handling that deals

 * 'with INSERT and UPDATE actions and the docid passed to DBWriter

 * '

 * 'Revision 1.13.2.5  2000/06/25 23:38:16  jones

 * 'Added RCSfile keyword

 * '

 * 'Revision 1.13.2.4  2000/06/25 23:34:17  jones

 * 'Changed documentation formatting, added log entries at bottom of source files

 * ''

 */