Metacat

/**

 *      Name: DBWriter.java

 *   Purpose: A Class that reads in an XML text document and

 *            write its contents to a database connection using SAX

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

 *            National Center for Ecological Analysis and Synthesis

 *   Authors: Matt Jones

 *

 *   Version: '$Id: DBWriter.java 186 2000-06-23 19:09:56Z jones $'

 */

package edu.ucsb.nceas.metacat;

import java.io.*;

import java.sql.*;

import java.util.Stack;

import org.xml.sax.AttributeList;

import org.xml.sax.ContentHandler;

import org.xml.sax.DTDHandler;

import org.xml.sax.EntityResolver;

import org.xml.sax.ErrorHandler;

import org.xml.sax.InputSource;

import org.xml.sax.XMLReader;

import org.xml.sax.SAXException;

import org.xml.sax.SAXParseException;

import org.xml.sax.helpers.XMLReaderFactory;

/**

 * A Class that reads in an XML text document and

 * write its contents to a database connection using SAX

 */

public class DBWriter {

  private Connection	conn = null;

  private String parserName = null;

  /** Default parser name. */

  private static final String

      DEFAULT_PARSER = "org.apache.xerces.parsers.SAXParser";

      //DEFAULT_PARSER = "oracle.xml.parser.v2.SAXParser";

  /**

   * the main routine used to test the DBWriter utility.

   * <p>

   * Usage: java DBWriter <filename>

   *

   * @param filename the filename to be loaded into the database

   */

  static public void main(String[] args) {

     if (args.length < 1)

     {

        System.err.println("Wrong number of arguments!!!");

        System.err.println("USAGE: java DBWriter <filename>");

        return;

     } else {

        try {

          String filename = args[0];

          // Open a connection to the database

          MetaCatUtil   util = new MetaCatUtil();

          Connection dbconn = util.openDBConnection();

          new DBWriter(filename, dbconn, DEFAULT_PARSER);

          System.out.println("Document processing finished for: " + filename);

        } catch (Exception e) {

          System.err.println("EXCEPTION HANDLING REQUIRED");

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

          e.printStackTrace(System.err);

        }

     }

  }

  /**

   * construct a new instance of the class to write an XML file to the database

   *

   * @param xml the xml stream to be loaded into the database

   * @param conn the database connection to which to write the XML file

   * @param parserName the name of a SAX2 compliant parser class

   */

  public DBWriter( Reader xml, Connection conn, String parserName)

                  throws IOException, 

                         SQLException, 

                         ClassNotFoundException {

    this.conn = conn;

    this.parserName = parserName;

    try {

        XMLReader parser = initializeParser();

        conn.setAutoCommit(false);

        parser.parse(new InputSource(xml));

        conn.commit();

        conn.setAutoCommit(true);

      } catch (SAXParseException e) {

        conn.rollback();

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

      } catch (SAXException e) {

        conn.rollback();

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

      } catch (Exception e) {

        conn.rollback();

        System.err.println(e.toString());

      }

  }

  /**

   * construct a new instance of the class to write an XML file to the database

   *

   * @param filename the filename to be loaded into the database

   * @param conn the database connection to which to write the XML file

   * @param parserName the name of a SAX2 compliant parser class

   */

  public DBWriter( String filename, Connection conn, String parserName)

                  throws IOException, 

                         SQLException, 

                         ClassNotFoundException {

     this(new FileReader(new File(filename).toString()), conn, parserName);

  }

  private XMLReader initializeParser() {

    XMLReader parser = null;

    //

    // Set up the SAX document handlers for parsing

    //

    try {

      ContentHandler xmlDocHandler = new DBSAXHandler(conn);

      EntityResolver xmlEntityResolver = new DBEntityResolver(conn);

      DTDHandler xmlDTDHandler         = new DBDTDHandler(conn);

      // Get an instance of the parser

      parser = XMLReaderFactory.createXMLReader(parserName);

      // Turn off validation

      parser.setFeature("http://xml.org/sax/features/validation", false);

      // Set Handlers in the parser

      parser.setProperty("http://xml.org/sax/properties/declaration-handler",

                         xmlDocHandler);

      parser.setProperty("http://xml.org/sax/properties/lexical-handler",

                         xmlDocHandler);

      parser.setContentHandler(xmlDocHandler);

      parser.setEntityResolver(xmlEntityResolver);

      parser.setDTDHandler(xmlDTDHandler);

      parser.setErrorHandler((ErrorHandler)xmlDocHandler);

    } catch (Exception e) {

       System.err.println(e.toString());

    }

    return parser;

  }

}