Metacat

/**

 *  '$RCSfile$'

 *    Purpose: A class that gets Accession Number, check for uniqueness

 *             and register it into db

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

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Jivka Bojilova, Matt Jones

 *    Release: @release@

 *

 *   '$Author: bojilova $'

 *     '$Date: 2000-09-28 11:05:46 -0700 (Thu, 28 Sep 2000) $'

 * '$Revision: 476 $'

 */

package edu.ucsb.nceas.metacat;

import java.net.*;

import java.sql.*;

/**

 * (on insert of XML document)

 * Generates a unique Accession Number or if provided check it 

 * for uniqueness and register it into the db connection 

 * (on update or delete of XML document)

 * Check for existance of provided Accession Number

 * 

 */

public class AccessionNumber  {

  private Connection conn = null;

  private String defaultGlobalName = null;

  private String sep = null;

  /** 

   * Construct an AccessionNumber 

   */

  public AccessionNumber () 

         throws SQLException, ClassNotFoundException  {

    MetaCatUtil util = new MetaCatUtil();

    this.defaultGlobalName = util.getOption("defaultGlobalName");

    this.sep = util.getOption("accNumberSeparator");

    // Open a connection to the database

    this.conn = util.openDBConnection();

  }  

  /** 

   * Construct an AccessionNumber

   *

   * @param conn the db connection to read from and write Accession# to

   */

  public AccessionNumber (Connection conn) {

    MetaCatUtil util = new MetaCatUtil();

    this.defaultGlobalName = util.getOption("defaultGlobalName");

    this.sep = util.getOption("accNumberSeparator");

    this.conn = conn;

  }

  /**

   * Get an Accession Number, check it for uniqueness and 

   * register it into db connection. If no Accession Number is

   * provided, generate one from the database and return it.

   *

   * @param accNumber - Accession # if provided or null if not

   * @param action - INSERT, UPDATE or DELETE.

   * When "INSERT" and accession # provided is not unique, get new one.

   * If it is unique, use it.

   * When "INSERT" and accession # is null, get a new one.

   * When "UPDATE", accession # is required and it is checked for existance.

   * When "DELETE", accession # is required and it is checked for existance.

   */

  public String generate (String accNumber, String action) 

         throws AccessionNumberException, SQLException   {

    String globalName = null;

    String localId = null;

    try {

      conn.setAutoCommit(true);

      // split the acc # in 2 parts - global name & local id

      if ( accNumber != null ) {

        globalName = getGlobalName(accNumber, sep);

        localId = getLocalId(accNumber, sep);

      }    

      // INSERT

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

        // get a unique Acc#

        if ( accNumber == null ) {

          return put(defaultGlobalName, null, sep);

        // Acc# is not used; return it

        } else if ( !accNumberUsed(globalName, localId) ) {

          return put(globalName, localId, sep);

        // Acc# is used; throw an exception to prevent the insertion

        } else {

          throw 

          new AccessionNumberException("Accession number is already in use.");

        }

      // UPDATE or DELETE

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

        // Acc# is not provided; throw an exception to prevent the action

        if ( accNumber == null ) {

          throw (new AccessionNumberException("Accession number is " +

          "required."));

        // Acc# is not current (not in xml_documents); throw an exception

        } else if (!accNumberIsCurrent(accNumber)) {

          throw (new AccessionNumberException("Document " +

          "not found for accession #: " + accNumber));

        // Acc# is current; return it

        } else {

          return accNumber;

        }

      }

      //conn.close();        

    } catch (StringIndexOutOfBoundsException siobe) {

      MetaCatUtil.debugMessage(

                 "Error on AccessionNumber.generate(): " + 

                  siobe.getMessage());

      throw (new AccessionNumberException("Accession number invalid, " +

                 "expecting character \'" + sep + "'."));

    } catch (SQLException e) {

      throw new SQLException(

                 "Error on AccessionNumber.generate(accNumber, action): " +

                  e.getMessage());

    }    

    throw (new AccessionNumberException("Fatal Error in " +

           "accession number generation: "));

  }    

  /** put unique accession # into db connection */

  private String put (String globalName, String localId, String sep) 

                throws SQLException

  {

    Integer l = null;

    try {

      if ( localId == null ) 

         l = new Integer(get(globalName) + 1); 

      //else if ( accNumberUsed(globalName, localId) )

      //   l = new Integer(get(globalName) + 1); 

      else

         l = new Integer(localId); 

     // insert globalName & l

     PreparedStatement pstmt;

     pstmt = conn.prepareStatement(

             "INSERT INTO xml_acc_numbers (global_name, local_id) " + 

             "VALUES (?, ?)");

     pstmt.setString(1,globalName);

     pstmt.setString(2,l.toString());

     pstmt.execute();

     pstmt.close();

    } catch (SQLException e) {

      throw new SQLException(

            "Error on AccessionNumber.put(globalName, localId, sep): " 

            + e.getMessage());

    }    

    return globalName + sep + l;

  }

  /** check for existence of Accesssion Number xml_acc_numbers table */

  private boolean accNumberUsed(String globalName, String localId)

                      throws SQLException {

    boolean hasAccNumber = false;

    try {

      PreparedStatement pstmt;

      pstmt = conn.prepareStatement(

                "SELECT 'x' FROM xml_acc_numbers " + 

                "WHERE global_name LIKE ? AND local_id = ?");

      pstmt.setString(1,globalName);

      pstmt.setString(2,localId);

      pstmt.execute();

      ResultSet rs = pstmt.getResultSet();

      hasAccNumber = rs.next();

      pstmt.close();

    } catch (SQLException e) {

      throw new SQLException(

                "Error on AccessionNumber.accNumberUsed(globalName, " +

                  "localId): " + e.getMessage());

    }    

    return hasAccNumber;

  }    

  /** check for existence of Accesssion Number in xml_documents table */

  private boolean accNumberIsCurrent(String accNumber) throws SQLException {

    boolean hasCurrentAccNumber = false;

    try {

      PreparedStatement pstmt;

      pstmt = conn.prepareStatement(

                "SELECT 'x' FROM xml_documents " + 

                "WHERE docid LIKE ?");

      pstmt.setString(1, accNumber);

      pstmt.execute();

      ResultSet rs = pstmt.getResultSet();

      hasCurrentAccNumber = rs.next();

      pstmt.close();

    } catch (SQLException e) {

      throw new SQLException(

          "Error on AccessionNumber.accNumberIsCurrent(String accNumber): " +

          e.getMessage());

    }    

    return hasCurrentAccNumber;

  }    

  /** get the last in order local ID by a given global name */

  private int get (String globalName) throws SQLException  {

    try {

      PreparedStatement pstmt;

      pstmt = conn.prepareStatement(

              "SELECT max(local_id) FROM xml_acc_numbers " + 

              "WHERE global_name LIKE ?");

      pstmt.setString(1,globalName);

      pstmt.execute();

      ResultSet rs = pstmt.getResultSet();

      boolean hasLocalId = rs.next();

      if (hasLocalId) {

        return rs.getInt(1);

      }

      pstmt.close();

    } catch (SQLException e) {

      throw new SQLException(

            "Error on AccessionNumber.get(globalName): " + e.getMessage());

    }    

    return 0;

  }

  // get the global part of the accession number

  private String getGlobalName (String accNumber, String sep) 

          throws StringIndexOutOfBoundsException {

    return accNumber.substring(0, accNumber.lastIndexOf(sep));

  }    

  // get the local part of the accession number

  private String getLocalId (String accNumber, String sep)

          throws StringIndexOutOfBoundsException {

    return accNumber.substring(accNumber.lastIndexOf(sep)+1);

  }    

}

/**

 * '$Log$

 * 'Revision 1.13  2000/09/20 20:15:58  bojilova

 * 'change Assession# generation to use the same db connection

 * '

 * 'Revision 1.12  2000/08/30 18:19:41  bojilova

 * 'cleared static methods in AccessionNumber classes for fixing bug found

 * 'when multiple requests to the servlet at a time.

 * '

 * 'Revision 1.11  2000/08/14 20:53:33  jones

 * 'Added "release" keyword to all metacat source files so that the release

 * 'number will be evident in software distributions.

 * '

 * 'Revision 1.10  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 1.9  2000/06/26 10:35:04  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 1.8.2.5  2000/06/26 08:38:01  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 1.8.2.4  2000/06/25 23:11:40  jones

 * 'Documentation update

 * '

 * 'Revision 1.8.2.3  2000/06/25 23:08:31  jones

 * 'Minor change to excpetion handling

 * ''

 */