jacsonstatefilter.java

java编写的OCR软件

/*
 * JacsonStateFilter.java
 *
 * Created on 26. Januar 2003, 22:44
 */

package de.spieleck.app.jacson.filter;

import java.util.Arrays;
import java.util.Iterator;

import gnu.trove.THashSet;

import de.spieleck.config.ConfigNode;

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;

/**
 * Filtering chunks depending on the current JacsonState
 * @author  Patrick Carl
 * @author fsn
 */
public class JacsonStateFilter 
    extends ConstFilter 
{
    /** This node determines which attribute of the JacsonState is examined */
    public final static String PARAMETER_NAME_NODE = "stateParameterName";
    /** These node determines the values which are accepted.  */
    public final static String PARAMETER_VALUE_NODE = "stateParameterValue";

    /**
     * if more possible values of the parameter exists than LIMIT is, then 
     * a THashSet will be used to store the values, otherwise an Array is used 
     */
    public final static int LIMIT = 6;
    
    
    /**
     * the parameter which is examined to determine whether a chunk is filtered
     * or not
     */
    protected String parameterName = null;
    protected String[] parameterValue = null;
    protected THashSet parameterValueSet = null;
    protected boolean usingArray;
    
    /** Creates a new instance of JacsonStateFilter */
    public JacsonStateFilter() { }
    
    public void init(ConfigNode config, JacsonRegistry registry)
        throws JacsonConfigException
    {
        super.init(config, registry);
        parameterName = config.getString(PARAMETER_NAME_NODE, null);
        if ( parameterName == null )
            throw new JacsonConfigException("JacsonStateFilter needs one "
                                                      +PARAMETER_NAME_NODE);
        int c = config.countChildrenNamed(PARAMETER_VALUE_NODE);
        if ( c == 0 )
            throw new JacsonConfigException("JacsonStateFilter needs at least one "
                                                      +PARAMETER_VALUE_NODE);
        usingArray = (c <= LIMIT);
        parameterValue  = new String[c];
        Iterator it = config.childrenNamed(PARAMETER_VALUE_NODE);
        int i = 0;
        while ( it.hasNext() )
        {
            parameterValue[i++] = (String) it.next();
        }
        if(!usingArray){
            parameterValueSet = new THashSet(Arrays.asList(parameterValue));
            parameterValue = null;
        }
        ConfigUtil.verify(config, this);
    }
    
    public boolean accept(ConfigNode node){
        String name = node.getName();
        return super.accept(node) || name.equals(PARAMETER_NAME_NODE) ||
        name.equals(PARAMETER_VALUE_NODE);
    }
    
    public void putChunk(String chunk)
        throws JacsonException 
    {
        String value = (String) getRegState().get(parameterName);
        
        if(value == null)
        {
            return;
        }

        if ( usingArray )
        {
            int i = 0;
            while ( i < parameterValue.length ) {
                if ( parameterValue[i].equals(value) ) 
                    break;
                i++;
            }
            if ( i < parameterValue.length ^ inverse)
                drain.putChunk(chunk);

        } else{
            if ( parameterValueSet.contains(value) ^ inverse)
                drain.putChunk(chunk);
        }
    }
}