Configuration

/**
 * XML parser for configuration parameters.
 *
 * This maps configuration parameters to a HashMap and are retrieved
 * through the following getter methods:
 *
 *     public String getLogFile()
 *     public String getDocumentRoot()
 *     public String getDefaultDocument()
 *     public String getServerName()
 *
 * Usage:
 *     Configuration config = new Configuration();
 *
 *    config.getLogFile();
 *    config.getDocumentRoot();
 *    config.getDefaultDocument();
 *    config.getServerName();
 */

import java.io.*;

import org.xml.sax.*;
import org.xml.sax.helpers.DefaultHandler;

import javax.xml.parsers.SAXParserFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;

import java.util.Map;
import java.util.HashMap;

public class Configuration extends DefaultHandler
{
    private Map  map;
    private String configurationFile;

    /**
     * @param File configurationFile - The name of the configuration file
     */
    public Configuration(String configurationFile) throws ConfigurationException {
    this.configurationFile = configurationFile;

    map = new HashMap();

    try {       
            // Use the default (non-validating) parser
            SAXParserFactory factory = SAXParserFactory.newInstance();

            // Parse the input
            SAXParser saxParser = factory.newSAXParser();
            saxParser.parse( new File(configurationFile), this);
    }
    catch (javax.xml.parsers.ParserConfigurationException pce) {
        throw new ConfigurationException("javax.xml.parsers.ParserConfigurationException");
    }
    catch (org.xml.sax.SAXException se) {
        throw new ConfigurationException("org.xml.sax.SAXException");
    }
    catch (java.io.IOException ioe) {
        throw new ConfigurationException("java.io.IOException");
    }
    }


    /**
     * We will map each configuration attribute to its value
     *
     * @param namespaceURI the namespace
     * @param lName the local name of the element
     * @param qName the qualified name of the element
     * @param attrs the set of attributess associated with the element
      */
    public void startElement(String namespaceURI,
                             String lName,    
                             String qName,    
                             Attributes attrs)   
    throws SAXException
    {
        String elementName = lName; // element name
        if ("".equals(elementName))
        elementName = qName; // namespaceAware = false

    /**
     * Get the attributes associated with this ELEMENT.
      * Attributes are name/value pairs and are stored by index.
     */
        if (attrs != null) {
            for (int i = 0; i < attrs.getLength(); i++) {
                String aName = attrs.getLocalName(i); // Attr name
                if ("".equals(aName))
            aName = attrs.getQName(i);

        // map the element.attribute to its value
        map.put(elementName+"."+aName,attrs.getValue(i));
            }
        }
    }

    // getter methods for mapped configuration values

    /** Returns the location of the log file */
    public String getLogFile() {
        return map.get("logfile.log");
    }

    /** Returns the location of the document base */
    public String getDocumentRoot() {
        return map.get("context.documentRoot");
    }

    /** Returns the name of the default document */
    public String getDefaultDocument() {
        return map.get("context.defaultDocument");
    }

    /** Returns the name of the server */
    public String getServerName() {
        return map.get("webserver.title");
    }
   
    /** Returns the name of the 400 file */
    public String get400()
    {
        return map.get("context.fourHundredDocument");
    }
   
    /** Returns the name of the 404 file */
    public String get404()
    {
        return map.get("context.fourOhFourDocument");
    }
}