config.java

java编写的OCR软件

package de.spieleck.config;

import java.io.IOException;

import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

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

import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

/**
 * Manager and Factory for Configurations.
 * @author fsn
 * @version ?
 */
public class Config
{
    /** Registered listeners for change of data */
    protected static List listeners;

    /**
     * Semi-Singleton: The default setup is an singleton while still
     * many setup objects may coexist.
     */
    protected static ConfigFileNode defaultConfig = null;

    /** Cannot construct this from externally */
    private Config() { }

    /**
     * Parse setup tree from an InputSource without {@link ConfigParamMap}
     * @return a freshly parsed {@link ConfigFileNode}
     */
    public static ConfigFileNode parse(InputSource is)
     throws IOException, SAXException
    {
        return parse(is, NullParamMap.getInstance());
    }

    /**
     * Parse setup tree from an InputSource with {@link ConfigParamMap}
     * @return a freshly parsed {@link ConfigFileNode}
     */
    public static ConfigFileNode parse(InputSource is, ConfigParamMap pm)
     throws IOException, SAXException
    {
        ConfigFileNode top       = new ConfigFileNode(null, null, 
                                                      is.getSystemId(), pm);
        ConfigBuilder builder = new ConfigBuilder(top, pm);
        try
        {
            SAXParser parser = newSAXParser();
            parser.parse(is, builder);
        }
        catch (Exception e)
        {
            e.printStackTrace();
            throw new SAXException(e);
        }
        return top;
    }


    /** 
     * Obtain a new parser.
     * @return a new SAXParser
     */
    protected static synchronized SAXParser newSAXParser()
     throws SAXException, ParserConfigurationException
    {
        SAXParserFactory spf = SAXParserFactory.newInstance();
        spf.setNamespaceAware(false);
        spf.setValidating(false);
        return spf.newSAXParser();
    }

    /**
     * Set the global visible (singleton) config node.
     */
    public static synchronized ConfigNode setConfig(ConfigFileNode setup)
    {
        ConfigFileNode old = defaultConfig;
        defaultConfig = setup;
        handleChange(setup);
        return old;
    }

    /**
     * Get the global visible (singleton) config node.
     * @return the global ConfigNode
     */
    public static synchronized ConfigNode getConfig()
    {
        return defaultConfig;
    }

    /**
   * We supply a preliminary api to inform listeners about a
   * change in configuration.
   */
    public synchronized static void addListener(ConfigListener listener)
    {
        if (listeners == null)
            listeners = new LinkedList();
        listeners.add(listener);
    }

    public synchronized static void removeListener(ConfigListener listener)
    {
        if (listeners != null)
            listeners.remove(listener);
    }

    protected static void handleChange(ConfigNode s)
    {
        if (listeners == null)
            return;
        Iterator e = listeners.iterator();
        while (e.hasNext())
        {
            ConfigListener listener = (ConfigListener)e.next();
            listener.handleConfigChange(s);
        }
    }
}
//
//    Jacson - Text Filtering with Java.
//    Copyright (C) 2002 Frank S. Nestel (nestefan -at- users.sourceforge.net)
//
//    This library is free software; you can redistribute it and/or
//    modify it under the terms of the GNU Lesser General Public
//    License as published by the Free Software Foundation; either
//    version 2.1 of the License, or (at your option) any later version.
//
//    This library 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
//    Lesser General Public License for more details.
//
//    You should have received a copy of the GNU Lesser General Public
//    License along with this library; if not, write to the Free Software
//    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//