substitutionfilter.java

java编写的OCR软件

package de.spieleck.app.jacson.filter;

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

import de.spieleck.config.ConfigNode;
import de.spieleck.config.ConfigVerify.Acceptor;

import de.spieleck.app.jacson.JacsonException;
import de.spieleck.app.jacson.JacsonConfigException;
import de.spieleck.app.jacson.JacsonRegistry;
import de.spieleck.app.jacson.util.ConfigUtil;

/**
 * A filter which accepts certains chunks and replaces
 * it by different ones. Configuration:
 * <ul>
 *  <li>Optional <onlymatches>: Non matches are blocked, default true.</li>
 * </ul>
 * This filter is particularly useful in conjunction with the
 * {@link SelectionFilterFilter} since one can modify
 * parts of a chunk and the continue processing.
 * @author fsn
 */
public class SubstitutionFilter
    extends FilterBase
    implements Acceptor
{
    public final static String ONLYMATCH_NODE = "onlymatch";
    public final static String MAP_NODE = "map";
    public final static String OLD_NODE = "old";
    public final static String NEW_NODE = "new";

    /** Do we let through chunks which do not match?? */
    protected boolean onlymatch;

    /** The mappings applied to the chunks. */
    protected Map map;

    public void init(ConfigNode config, JacsonRegistry registry)
        throws JacsonConfigException
    {
        onlymatch = config.getBoolean("onlymatch", false);
        map = new HashMap();
        Iterator it = config.childrenNamed("map");
        if ( !it.hasNext() )
            throw new JacsonConfigException("Missing mapping for SubstitutionFilter");
        while ( it.hasNext() )
        {
            ConfigNode cn = (ConfigNode) it.next();
            String old = cn.getString(OLD_NODE, null);
            String neu = cn.getString(NEW_NODE, null);
            if ( old != null && neu != null )
                map.put(old, neu);
            else
                throw new JacsonConfigException("Missing <"+old+"> -> <"+neu+">.");
        }
        ConfigUtil.verify(config, this);
    }

    public boolean accept(ConfigNode node)
    {
        String name = node.getName();
        return ONLYMATCH_NODE.equals(name)
            || MAP_NODE.equals(name);
    }

    public void putChunk(String chunk)
        throws JacsonException
    {
        if ( chunk == null )
        {
            drain.putChunk(chunk);
        }
        else
        {
            String neu = (String) map.get(chunk);
            if ( neu != null )
                drain.putChunk( neu );
            else if ( onlymatch )
                return;
            else
                drain.putChunk(chunk);
        }
    }
}
//
//    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
//