Metacat

/**

 *  '$RCSfile$'

 *    Purpose: A Class that represents an XML Text node and its contents,

 *             and can build itself from a database connection

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

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Matt Jones

 *    Release: @release@

 *

 *   '$Author: sgarg $'

 *     '$Date: 2004-08-19 18:09:25 -0700 (Thu, 19 Aug 2004) $'

 * '$Revision: 2245 $'

 *

 * 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 java.util.Comparator;

import java.util.Stack;

import java.sql.PreparedStatement;

import java.sql.SQLException;

import java.sql.ResultSet;

import org.xml.sax.SAXException;

/**

 * A Class that represents an XML Subtree

 */

public class SubTree implements Comparator

{

  protected String docId = null;

  protected String subTreeId = null;

  protected String startElementName = null;

  protected long   startNodeId = -1;

  protected long   endNodeId =   -1;

  private Stack  subTreeNodeStack = null;

    /**

     * Defualt constructor

     */

    public SubTree()

    {

    }

    /**

     * Constructor of subtree

     */

    public SubTree(String myDocId, String mySubTreeId,

                  long myStartNodeId, long myEndNodeId)

    {

      this.docId = myDocId;

      MetaCatUtil.debugMessage("Docid of Subtree: " + docId, 30);

      this.subTreeId = mySubTreeId;

      MetaCatUtil.debugMessage("id of Subtree: " + subTreeId, 30);

      this.startNodeId = myStartNodeId;

      MetaCatUtil.debugMessage("start node id of Subtree: " + startNodeId, 30);

      this.endNodeId = myEndNodeId;

      MetaCatUtil.debugMessage("end node id of subtree: " + endNodeId, 30);

    }

    /**

     * Get subtree node stack

     */

    public Stack getSubTreeNodeStack() throws SAXException

    {

      try

      {

        subTreeNodeStack = getSubTreeNodeList();

      }

      catch (McdbException e)

      {

        throw new SAXException(e.getMessage());

      }

      return this.subTreeNodeStack;

    }

    /**

     * Set subtree node stack

     */

    public void setSubTreeNodeStack(Stack myStack)

    {

      this.subTreeNodeStack = myStack;

    }

    /** Set the a docId */

    public void setDocId(String myId)

    {

      MetaCatUtil.debugMessage("set doc id: "+myId, 35);

      this.docId = myId;

    }

    /** Get the docId */

    public String getDocId()

    {

      return this.docId;

    }

    /** Set the a subtreeId */

    public void setSubTreeId(String myId)

    {

      MetaCatUtil.debugMessage("set sub tree id: "+myId, 35);

      this.subTreeId = myId;

    }

    /** Get the subTreeId */

    public String getSubTreeId()

    {

      return this.subTreeId;

    }

    /**

     * Set a startElementName

     */

    public void setStartElementName(String elementName)

    {

      MetaCatUtil.debugMessage("set start elementname: "+elementName, 35);

      this.startElementName = elementName;

    }

    /**

     * Get startElementName

     */

    public String getStartElementName()

    {

      return this.startElementName;

    }

    /** Set a start node id */

    public void setStartNodeId(long nodeId)

    {

      MetaCatUtil.debugMessage("set start node id: "+nodeId, 35);

      this.startNodeId = nodeId;

    }

    /** Get start node id */

    public long getStartNodeId()

    {

      return this.startNodeId;

    }

    /** Set a end node id */

    public void setEndNodeId(long nodeId)

    {

      MetaCatUtil.debugMessage("set end node id: "+nodeId, 35);

      this.endNodeId = nodeId;

    }

    /** Get end node id */

    public long getEndNodeId()

    {

      return this.endNodeId;

    }

    /* Put a subtree node into a stack, on top is the start point of subtree*/

    private Stack getSubTreeNodeList() throws McdbException

    {

       Stack nodeRecordList = new Stack();

       // make sure it works

       if ( docId == null || startNodeId == -1 || endNodeId == -1)

       {

         return nodeRecordList;

       }

       PreparedStatement pstmt = null;

       DBConnection dbconn = null;

       int serialNumber = -1;

       long nodeid = 0;

       long parentnodeid = 0;

       long nodeindex = 0;

       String nodetype = null;

       String nodename = null;

       String nodeprefix = null;

       String nodedata = null;

       String sql = "SELECT nodeid, parentnodeid, nodeindex, " +

                    "nodetype, nodename, nodeprefix, nodedata " +

                    "FROM xml_nodes WHERE docid = ? AND nodeid >= ? AND " +

                    "nodeid <= ? ORDER BY nodeid DESC";

       try

       {

         dbconn=DBConnectionPool.

                    getDBConnection("SubTree.getSubTreeNodeList");

         serialNumber=dbconn.getCheckOutSerialNumber();

         pstmt = dbconn.prepareStatement(sql);

         // Bind the values to the query

         pstmt.setString(1, docId);

         pstmt.setLong(2, startNodeId);

         pstmt.setLong(3, endNodeId);

         pstmt.execute();

         ResultSet rs = pstmt.getResultSet();

         boolean tableHasRows = rs.next();

         while (tableHasRows)

         {

           nodeid = rs.getLong(1);

           parentnodeid = rs.getLong(2);

           nodeindex = rs.getLong(3);

           nodetype = rs.getString(4);

           nodename = rs.getString(5);

           nodeprefix = rs.getString(6);

           nodedata = rs.getString(7);

           nodedata = MetaCatUtil.normalize(nodedata);

           // add the data to the node record list hashtable

           NodeRecord currentRecord = new NodeRecord(nodeid,parentnodeid,nodeindex,

                                      nodetype, nodename, nodeprefix, nodedata);

           nodeRecordList.push(currentRecord);

           // Advance to the next node

           tableHasRows = rs.next();

         }//while

         pstmt.close();

      } //try

      catch (SQLException e)

      {

        throw new McdbException("Error in SubTree.getSubTreeNodeList 1 " +

                              e.getMessage());

      }//catch

      finally

      {

        try

        {

          pstmt.close();

        }

        catch (SQLException ee)

        {

          MetaCatUtil.debugMessage("error in SubTree.getSubTreeNodeList 2: "

                                    +ee.getMessage(), 30);

        }

        finally

        {

          DBConnectionPool.returnDBConnection(dbconn, serialNumber);

        }

      }//finally

      return nodeRecordList;

    }//getSubtreeNodeList

   /** methods from Comparator interface */

   public int compare(Object o1, Object o2)

   {

     SubTree tree1 = (SubTree) o1;

     SubTree tree2 = (SubTree) o2;

     if (tree1.getStartNodeId() > tree2.getStartNodeId())

     {

       return 1;

     }

     else if (tree1.getStartNodeId() < tree2.getStartNodeId())

     {

       return -1;

     }

     else

     {

       return 0;

     }

   }//cpmpare

   /** method from Comparator interface */

   public boolean equals(Object obj)

   {

     SubTree tree = (SubTree)obj;

     if (startNodeId == tree.getStartNodeId())

     {

       return true;

     }

     else

     {

       return false;

     }

   }

}