package io;

import java.io.File;
import java.io.FilenameFilter;
import util.RegularExpr;

/**
 * This is regular expression filename filter. 
 * 
 * @author <a href="mailto:rana_b@yahoo.com">Rana Bhattacharyya</a>
 */
public
class FileRegularFilter implements FilenameFilter {
    
    private RegularExpr mRegularExpr = null;
    
    /**
     * Constructor.
     * @param pattern regular expression
     */
    public FileRegularFilter(String pattern) {
        if ((pattern == null) || pattern.equals("") || pattern.equals("*")) {
            mRegularExpr = null;
        }
        else {
            mRegularExpr = new RegularExpr(pattern);
        }
    }
    
    /**
     * Tests if a specified file should be included in a file list.
     * @param dir - the directory in which the file was found
     * @param name - the name of the file.
     */
    public boolean accept(File dir, String name) {
        if (mRegularExpr == null) {
            return true;
        }
        return mRegularExpr.isMatch(name);
    }
}