Metacat

/**

 *   '$Author: daigle $'

 *     '$Date: 2008-08-05 17:50:14 -0700 (Tue, 05 Aug 2008) $'

 * '$Revision: 4213 $'

 *

 * 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 edu.ucsb.nceas.metacat.service.PropertyService;

import edu.ucsb.nceas.metacat.util.MetaCatUtil;

import edu.ucsb.nceas.morpho.datapackage.Triple;

import edu.ucsb.nceas.morpho.datapackage.TripleCollection;

import edu.ucsb.nceas.utilities.PropertyNotFoundException;

import java.io.StringReader;

import java.sql.*;

import java.util.*;

import java.net.*;

import org.apache.log4j.Logger;

public class RelationHandler //implements Runnable

{

  private DBConnection connection = null;

  private String docid = null;

  private String docType = null;

  private static Logger logMetacat = Logger.getLogger(RelationHandler.class);

  TripleCollection tripleForPackage = null;

  /** 

   * Constructor for this class.  finds all of the relations to a single xml

   * document and writes them to the database.  This includes transitive

   * relations.

   * @param docid the ID of the XML document to index.

   * @param doctype the doctype of this document

   * @param conn the db connection

   * @param list the triple list

   */

  public RelationHandler(String docid, String doctype, 

                        DBConnection conn, TripleCollection list)

              throws McdbException, SQLException, AccessionNumberException

  {

    this.connection = conn;

    this.docid = docid;

    this.docType = doctype;

    tripleForPackage = list;

    createRelations();

  }

   /**

   * insert the relations specified in the triples into xml_relation table

   */ 

  private void createRelations() 

              throws McdbException, SQLException, AccessionNumberException

  {

    String packagetype = docType;

    String subject = null;

    String subjectParentId = null;

    String subDoctype = null;

    String relationship = null;

    String relationshipParentId = null;

    String object = null;

    String objDoctype = null;

    PreparedStatement tstmt = null; // to insert each relation into xml_relation

    logMetacat.info("Running relation handler!");

    // first delete the relations for this package document if any

    deleteRelations(docid);

    //get the vetor of triples 

    Vector tripleList= new Vector();

    //get vector form tripleCollection

    if (tripleForPackage != null)

    {

      tripleList =tripleForPackage.getCollection();

    }

    if (tripleList != null && tripleList.size()>0) 

    {

       tstmt = connection.prepareStatement("INSERT INTO xml_relation (" +

                                    "docid,packagetype,subject,subdoctype," +

                                    "relationship, object, objdoctype) " + 

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

      // go through tripe list 

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

      {

        //increase usage count

        connection.increaseUsageCount(1);

        // Get the triple

        Triple triple = (Triple)tripleList.elementAt(i);

        logMetacat.info("Info from triple: ");

        logMetacat.info("subject from triple:"+triple.getSubject());

        logMetacat.info("relationship from triple:"+triple.getRelationship());

        logMetacat.info("object from triple: "+triple.getObject());

        //subject = (new DocumentIdentifier(triple.getSubject())).getIdentifier();

        subject = MetaCatUtil.getDocIdFromString(triple.getSubject());

        relationship = triple.getRelationship();

        //object = (new DocumentIdentifier(triple.getObject())).getIdentifier();

        object = MetaCatUtil.getDocIdFromString(triple.getObject());

        if (subject != null && relationship != null && object != null)

        {

          //put the new relation into xml_relation

          logMetacat.info("Insert into xml_relation table");

          tstmt.setString(1, docid);

          logMetacat.info("Insert docid into xml_relation table" + 

                                docid);

          tstmt.setString(2, packagetype);

          tstmt.setString(3, subject);

          logMetacat.info("Insert subject into xml_relation table" + 

                               subject);

          tstmt.setString(4, subDoctype);

          tstmt.setString(5, relationship);

          logMetacat.info("Insert relationship into xml_relation table" + 

                                relationship);

          tstmt.setString(6, object);

          logMetacat.info("Insert object into xml_relation table" + 

                                object);

          tstmt.setString(7, objDoctype);

          tstmt.execute();  

        }//if

      }//for

    }//if

    if ( tstmt != null ) 

    {

      tstmt.close();

    }

  }

  /**

   * Deletes all of the relations with a docid of 'docid'.

   * @param docid the docid of the package which relations to delete.

   */

  public void deleteRelations(String docid) throws SQLException

  {

    try {

      PreparedStatement pstmt = connection.prepareStatement(

                                "DELETE FROM xml_relation " +

                                "WHERE docid = '" + docid + "'");

      //increase usage count

      connection.increaseUsageCount(1);

      pstmt.execute();

      pstmt.close();

    } catch(SQLException e) {

      logMetacat.error("error in RelationHandler.deleteRelations(): " + 

                          e.getMessage());

      throw e;

    }

  }

  /**

	 * Get the access file id for a package

	 * @param docid the document identifier of the package

	 * @return the document identifier of the access file for that package

	 */

	public static String getAccessFileIDWithRevision(String docid) throws SQLException {

		String aclid = null;

		int rev;

		PreparedStatement pstmt = null;

		DBConnection dbConn = null;

		int serialNumber = -1;

		StringBuffer sql = new StringBuffer();

		sql

				.append("SELECT docid, rev FROM xml_documents WHERE docid in (SELECT subject ");

		sql.append("FROM xml_relation WHERE docid='").append(docid);

		sql.append("' AND (");

		Vector accessdoctypes;

		try {

			accessdoctypes = MetaCatUtil.getOptionList(PropertyService

				.getProperty("xml.accessdoctype"));

		} catch (PropertyNotFoundException pnfe) {

			throw new SQLException("Could not find access doctype: " + pnfe.getMessage());

		}

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

			String atype = (String) accessdoctypes.elementAt(i);

			sql.append("doctype='").append(atype).append("'");

			if (i < accessdoctypes.size() - 1) {

				sql.append(" OR ");

			}

		}

		sql.append("))");

		//System.out.println("new sql script: " + sql.toString());

		try {

			dbConn = DBConnectionPool.getDBConnection("RelationHandler.getAccessFileID");

			serialNumber = dbConn.getCheckOutSerialNumber();

			pstmt = dbConn.prepareStatement(sql.toString());

			pstmt.execute();

			ResultSet rs = pstmt.getResultSet();

			boolean hasRow = rs.next();

			if (hasRow) {

				aclid = rs.getString(1);

				rev = rs.getInt(2);

				String sep = ".";

				try {

					sep = PropertyService.getProperty("document.accNumSeparator");

				} catch (PropertyNotFoundException pnfe) {

					logMetacat.error("Could not find account separator.  Setting to '.': " + pnfe.getMessage());

				}

				aclid = sep + rev;

			}

			pstmt.close();

		}//try

		finally {

			try {

				pstmt.close();

			}//try

			finally {

				DBConnectionPool.returnDBConnection(dbConn, serialNumber);

			}//finally

		}//finally

		logMetacat.info("The access docid get from xml_relation is: " + aclid);

		return aclid;

	}

}