sortfilter.java

java编写的OCR软件

/*
 * SortFilter.java
 *
 * Created on 28. September 2005, 21:01
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package de.spieleck.app.jacson.filter;

import de.spieleck.app.jacson.JacsonException;
import de.spieleck.app.jacson.JacsonRegistry;
import de.spieleck.config.ConfigNode;
import java.util.Comparator;
import java.util.Iterator;
import java.util.SortedSet;
import java.util.TreeSet;

/**
 * <h2>SortFilter</h2>
 * <h3>Description</h3>
 * <p>Filter class which sorts the incoming chunks</p>
 * <h3>Parameters</h3>
 * <table border="1" cellpadding="2" cellspacing="0">
 *  <tr>
 *   <td valign="top"><b>Attribute</b></td>
 *   <td valign="top"><b>Description</b></td>
 *   <td align="center" valign="top"><b>Required</b></td>
 *  </tr>
 *  <tr>
 *   <td valign="top">inverse</td>
 *   <td valign="top">If inverse is false the chunks are sorted in their
         natural order. If inverse is true, the order of chunks is inverted.</td>
 *   <td valign="top" align="center">No, default is false</td>
 *  </tr>
 * </table>
 * 
 * @version $Id: SortFilter.java 35 2005-10-03 22:08:55Z pcs $
 * @version since 0.90
 */
public class SortFilter extends ConstFilter {
    
    SortedSet buffer;
    
    public void putChunk(String chunk) throws JacsonException {
        if(chunk == null)
            feedChunks();
        else
            buffer.add(chunk);
    }
    
    public void init(ConfigNode config, JacsonRegistry registry) throws de.spieleck.app.jacson.JacsonConfigException {
        super.init(config, registry);
        //create a TreeSet with a specific comparator if inverse is true
        buffer = inverse ? new TreeSet(new Comparator(){
            public int compare(Object o1, Object o2){
                return -(((String) o1).compareTo((String) o2));
            }
        }) : new TreeSet();
        
    }
    
    /**
     * delivers the received chunks to the drain
     */
    private void feedChunks() throws JacsonException{
        Iterator it = buffer.iterator();
        while(it.hasNext())
            drain.putChunk((String)it.next());
        drain.putChunk(null);
    }
    
    
    
    
}