headfilter.java

java编写的OCR软件

package de.spieleck.app.jacson.filter;

import de.spieleck.config.ConfigNode;

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

/**
 * Filter to let through only the first few chunks.
 * (or all but the first few with inverse).
 * @author fsn
 */
public class HeadFilter
    extends ConstFilter
{
    public final static String COUNT_NODE = "count";
    public final static String RESET_NODE = "reset";

    /** number of chunks to be treated. */
    protected int head;

    /** Count of input chunks. */
    protected int count;

    /** Reset with a null chunk? default=true */
    protected boolean reset;

    public void init(ConfigNode config, JacsonRegistry registry)
        throws JacsonConfigException
    {
        head = config.getInt(COUNT_NODE, -1);
        if ( head < 0 )
            throw new JacsonConfigException("HeadFilter needs count > 0");
        reset = config.getBoolean(RESET_NODE, true);
        count = 0;
        super.init(config, registry);
    }

    public boolean accept(ConfigNode node)
    {
        String name = node.getName();
        return COUNT_NODE.equals(name) || RESET_NODE.equals(name)
            || super.accept(node);
    }

    public void putChunk(String chunk)
        throws JacsonException
    {
        if ( chunk == null )
        {
            drain.putChunk(chunk);
            if ( reset ) 
                count = 0;
        }
        else if ( ( count++ < head ) ^ inverse )
        {
            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
//