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/**
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 *        Name: DBElement.java
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 *     Purpose: A Class that represents an XML element and can
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 *		write its contents to a database connection
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 *   Copyright: 2000 Regents of the University of California and the
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 *              National Center for Ecological Analysis and Synthesis
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 *     Authors: Matt Jones
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 *
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 *     Version: '$Id: DBElement.java 52 2000-04-17 23:29:00Z jones $'
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 */
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import com.sun.xml.tree.ElementNode;
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import org.w3c.dom.DOMException;
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import org.w3c.dom.Element;
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import org.w3c.dom.Attr;
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import org.w3c.dom.Node;
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import org.w3c.dom.NodeList;
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import org.w3c.dom.NamedNodeMap;
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import org.w3c.dom.ProcessingInstruction;
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import org.w3c.dom.Text;
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import java.sql.*;
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import java.io.IOException;
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public class DBElement extends ElementNode {
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    public DBElement () {
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      super();
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    };
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    /**
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     * Writes this element and all of its children out to the 
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     * given database connection 
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     */
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    public void writeXmlToDB(Connection conn, int parentID) 
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		throws IOException {
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        int maxid=0;
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        int newid=0;
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        Statement stmt;
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        try {
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          stmt = conn.createStatement();
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          stmt.execute("SELECT MAX(nodeid) FROM xml_elements");
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          try {
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            ResultSet rs = stmt.getResultSet();
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            try {
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              boolean tableHasRows = rs.next();
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              if (tableHasRows) {
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                try {
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                  maxid = rs.getInt(1);
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                } catch (SQLException e) {
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                  System.out.println("Error with getInt: " + e.getMessage());
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                }
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              }
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            } catch (SQLException e) {
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              System.out.println("Error with next: " + e.getMessage());
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            }
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          } catch (SQLException e) {
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            System.out.println("Error with getrset: " + e.getMessage());
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          }
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          stmt.close();
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        } catch (SQLException e) {
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          System.out.println("Error getting id: " + e.getMessage());
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        }
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        // assign a new ID number
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        newid = maxid + 1;
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        try {
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          PreparedStatement pstmt;
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          if (parentID != 0) {
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            pstmt = conn.prepareStatement(
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                "INSERT INTO xml_elements(nodeid, nodename, parentnodeid) " + 
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		"VALUES (?, ?, ?)");
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          } else {
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            pstmt = conn.prepareStatement(
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                "INSERT INTO xml_elements(nodeid, nodename) " + 
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		"VALUES (?, ?)");
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          }
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          // Bind the values to the query
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          pstmt.setInt(1, newid); // The first ? is for NODEID
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          pstmt.setString(2, getTagName());// The second ? is for NODENAME
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          if (parentID != 0) {
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            pstmt.setInt(3, parentID);
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          }
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          // Do the insertion
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          pstmt.execute();
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          pstmt.close();
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        } catch (SQLException e) {
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          System.out.println(e.getMessage());
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        }
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        System.out.println("ID: " + newid + "\tTag: " + getTagName());
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        // Now save this node's attributes
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	writeAttributesToDB(conn, newid);
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        // Now save this node's children
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	if (hasChildNodes()) {
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            try {
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	      writeChildrenXmlToDB(conn, newid);
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            } catch (SQLException e) {
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              System.out.println(e.getMessage());
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            }
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        }
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    }
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    public void writeChildrenXmlToDB(Connection conn, int parentID) 
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		throws IOException, SQLException {
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      NodeList children = getChildNodes();
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      if (children != null) {
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        for (int i = 0; i < children.getLength(); i++) {
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          if (children.item(i) instanceof ElementNode) {
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            ((DBElement)children.item(i)).writeXmlToDB(conn, parentID);
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          } else if (children.item(i) instanceof Text) {
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             // Write the text to the now created parent node
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             PreparedStatement pstmt = conn.prepareStatement(
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                "UPDATE xml_elements SET nodedata = ? " + 
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		"WHERE nodeid = ?");
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             pstmt.setString(1, ((Text)children.item(i)).getNodeValue()); 
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             pstmt.setInt(2, parentID); 
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             pstmt.execute();
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             pstmt.close();
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          } else {
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            System.out.println("    Other Node Type skipped.");
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          }
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        }
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      }
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    }
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    /**
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     * Writes this element's attributes out to the 
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     * given database connection 
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     */
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    public void writeAttributesToDB(Connection conn, int nodeid) 
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		throws IOException {
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        NamedNodeMap attributes = getAttributes();
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        if (attributes != null) {
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            for (int i=0; i < attributes.getLength(); i++) {
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               String name = ((Attr)attributes.item(i)).getName();
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               String value = ((Attr)attributes.item(i)).getValue();
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               System.out.println("    Saving attribute: " + name + "=" + value);
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               int maxid=0;
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               int newid=0;
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               Statement stmt;
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               try {
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                 stmt = conn.createStatement();
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                 stmt.execute("SELECT MAX(attributeid) FROM xml_attributes");
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                 try {
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                   ResultSet rs = stmt.getResultSet();
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                   try {
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                     boolean tableHasRows = rs.next();
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                     if (tableHasRows) {
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                       try {
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                         maxid = rs.getInt(1);
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                       } catch (SQLException e) {
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                         System.out.println("Error with getInt: " + e.getMessage());
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                       }
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              }
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                   } catch (SQLException e) {
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                     System.out.println("Error with next: " + e.getMessage());
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                   }
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                 } catch (SQLException e) {
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                   System.out.println("Error with getrset: " + e.getMessage());
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                 }
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                 stmt.close();
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               } catch (SQLException e) {
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                 System.out.println("Error getting id: " + e.getMessage());
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               }
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               // assign a new ID number
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               newid = maxid + 1;
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               try {
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                 PreparedStatement pstmt;
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                 pstmt = conn.prepareStatement(
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                  "INSERT INTO xml_attributes(attributeid, nodeid, " +
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                  "attributenumber, attributename, attributevalue) " +
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		   "VALUES (?, ?, ?, ?, ?)");
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                 // Bind the values to the query
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                 pstmt.setInt(1, newid); 		// ATTRIBUTEID
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                 pstmt.setInt(2, nodeid);		// NODEID
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                 pstmt.setInt(3, i+1); 			// ATTRIBUTENUMBER
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                 pstmt.setString(4, name);		// ATTRIBUTENAME
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                 pstmt.setString(5, value);		// ATTRIBUTEVALUE
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                 // Do the insertion
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                 pstmt.execute();
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                 pstmt.close();
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               } catch (SQLException e) {
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                 System.out.println(e.getMessage());
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               }
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            }
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        }
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    }
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    // used by JTree to display this node
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    public String toString ()
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    {
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	StringBuffer	value = new StringBuffer ();
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	value.append ('<');
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	value.append (getTagName ());
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	value.append (getAttributes ().toString ());
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	value.append ('>');
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	return value.toString ();
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    }
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}
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