fileutil.java

java平台的图形音乐播放器

/*
 * FileUtil.
 * 
 * JavaZOOM : [e-mail]
 *            http://www.javazoom.net 
 *
 *-----------------------------------------------------------------------
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Library General Public License as published
 *   by the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program 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 Library General Public License for more details.
 *
 *   You should have received a copy of the GNU Library General Public
 *   License along with this program; if not, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *----------------------------------------------------------------------
 */
package javazoom.jlgui.player.amp.util;

import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.StringTokenizer;

/**
 * @author Scott Pennell
 */
public class FileUtil
{
    private static List supportedExtensions = null;

    public static File[] findFilesRecursively(File directory)
    {
        if (directory.isFile())
        {
            File[] f = new File[1];
            f[0] = directory;
            return f;
        }
        List list = new ArrayList();
        addSongsRecursive(list, directory);
        return ((File[]) list.toArray(new File[list.size()]));
    }

    private static void addSongsRecursive(List found, File rootDir)
    {
        if (rootDir == null) return; // we do not want waste time
        File[] files = rootDir.listFiles();
        if (files == null) return;
        for (int i = 0; i < files.length; i++)
        {
            File file = new File(rootDir, files[i].getName());
            if (file.isDirectory()) addSongsRecursive(found, file);
            else
            {
                if (isMusicFile(files[i]))
                {
                    found.add(file);
                }
            }
        }
    }

    public static boolean isMusicFile(File f)
    {
        List exts = getSupportedExtensions();
        int sz = exts.size();
        String ext;
        String name = f.getName();
        for (int i = 0; i < sz; i++)
        {
            ext = (String) exts.get(i);
            if (ext.equals(".wsz") || ext.equals(".m3u")) continue;
            if (name.endsWith(ext)) return true;
        }
        return false;
    }

    public static List getSupportedExtensions()
    {
        if (supportedExtensions == null)
        {
            String ext = Config.getInstance().getExtensions();
            StringTokenizer st = new StringTokenizer(ext, ",");
            supportedExtensions = new ArrayList();
            while (st.hasMoreTokens())
                supportedExtensions.add("." + st.nextElement());
        }
        return (supportedExtensions);
    }

    public static String getSupprtedExtensions()
    {
        List exts = getSupportedExtensions();
        StringBuffer s = new StringBuffer();
        int sz = exts.size();
        String ext;
        for (int i = 0; i < sz; i++)
        {
            ext = (String) exts.get(i);
            if (ext.equals(".wsz") || ext.equals(".m3u")) continue;
            if (i == 0) s.append(ext);
            else s.append(";").append(ext);
        }
        return s.toString();
    }

    public static String padString(String s, int length)
    {
        return padString(s, ' ', length);
    }

    public static String padString(String s, char padChar, int length)
    {
        int slen, numPads = 0;
        if (s == null)
        {
            s = "";
            numPads = length;
        }
        else if ((slen = s.length()) > length)
        {
            s = s.substring(0, length);
        }
        else if (slen < length)
        {
            numPads = length - slen;
        }
        if (numPads == 0) return s;
        char[] c = new char[numPads];
        Arrays.fill(c, padChar);
        return s + new String(c);
    }

    public static String rightPadString(String s, int length)
    {
        return (rightPadString(s, ' ', length));
    }

    public static String rightPadString(String s, char padChar, int length)
    {
        int slen, numPads = 0;
        if (s == null)
        {
            s = "";
            numPads = length;
        }
        else if ((slen = s.length()) > length)
        {
            s = s.substring(length);
        }
        else if (slen < length)
        {
            numPads = length - slen;
        }
        if (numPads == 0) return (s);
        char[] c = new char[numPads];
        Arrays.fill(c, padChar);
        return new String(c) + s;
    }
}